3D render in grass.jupyter fails due to missing dependencies

[wenzeslaus]

xvfb (apt-like dependency) and PyVirtualDisplay (pip-like dependency) are missing for running on nodes (that is without -X).

Running ./python/grass/jupyter/testsuite/test_render3d.py...
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ERROR: Bad server connection
EERROR: Bad server connection
EERROR: Bad server connection
EERROR: Bad server connection
EERROR: Bad server connection
Es.
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ERROR: test_defaults (__main__.TestDisplay)
Check that default settings work
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Traceback (most recent call last):
  File "python/grass/jupyter/testsuite/test_render3d.py", line 86, in test_defaults
    renderer.render(elevation_map="elevation", color_map="elevation")
  File "etc/python/grass/jupyter/render3d.py", line 213, in render
    gs.run_command(module, env=env, **kwargs)
  File "etc/python/grass/script/core.py", line 541, in run_command
    return handle_errors(returncode, result=None, args=args, kwargs=kwargs)
  File "etc/python/grass/script/core.py", line 429, in handle_errors
    raise CalledModuleError(module=module, code=code, returncode=returncode)
grass.exceptions.CalledModuleError: Module run `m.nviz.image elevation_map=elevation color_map=elevation output=/share/rkmeente/vpetras/tmp/grass8-vpetras-18913/tmpvz_0qwt5/nviz format=tif size=600,400 mode=fine resolution_fine=1` ended with an error.
The subprocess ended with a non-zero return code: 1. See errors above the traceback or in the error output.

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ERROR: test_filename (__main__.TestDisplay)
Check that custom filename works
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Traceback (most recent call last):
  File "python/grass/jupyter/testsuite/test_render3d.py", line 95, in test_filename
    renderer.render(elevation_map="elevation", color_map="elevation")
  File "etc/python/grass/jupyter/render3d.py", line 213, in render
    gs.run_command(module, env=env, **kwargs)
  File "etc/python/grass/script/core.py", line 541, in run_command
    return handle_errors(returncode, result=None, args=args, kwargs=kwargs)
  File "etc/python/grass/script/core.py", line 429, in handle_errors
    raise CalledModuleError(module=module, code=code, returncode=returncode)
grass.exceptions.CalledModuleError: Module run `m.nviz.image elevation_map=elevation color_map=elevation output=/share/rkmeente/vpetras/tmp/grass8-vpetras-18913/tmp1nneps7w/nviz format=tif size=600,400 mode=fine resolution_fine=1` ended with an error.
The subprocess ended with a non-zero return code: 1. See errors above the traceback or in the error output.

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ERROR: test_hw (__main__.TestDisplay)
Check that custom width and height works
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Traceback (most recent call last):
  File "python/grass/jupyter/testsuite/test_render3d.py", line 101, in test_hw
    renderer.render(elevation_map="elevation", color_map="elevation")
  File "etc/python/grass/jupyter/render3d.py", line 213, in render
    gs.run_command(module, env=env, **kwargs)
  File "etc/python/grass/script/core.py", line 541, in run_command
    return handle_errors(returncode, result=None, args=args, kwargs=kwargs)
  File "etc/python/grass/script/core.py", line 429, in handle_errors
    raise CalledModuleError(module=module, code=code, returncode=returncode)
grass.exceptions.CalledModuleError: Module run `m.nviz.image elevation_map=elevation color_map=elevation output=/share/rkmeente/vpetras/tmp/grass8-vpetras-18913/tmpaexifnvi/nviz format=tif size=200,400 mode=fine resolution_fine=1` ended with an error.
The subprocess ended with a non-zero return code: 1. See errors above the traceback or in the error output.

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ERROR: test_image_creation (__main__.TestDisplay)
Check that show() works
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Traceback (most recent call last):
  File "python/grass/jupyter/testsuite/test_render3d.py", line 129, in test_image_creation
    renderer.render(elevation_map="elevation", color_map="elevation")
  File "etc/python/grass/jupyter/render3d.py", line 213, in render
    gs.run_command(module, env=env, **kwargs)
  File "etc/python/grass/script/core.py", line 541, in run_command
    return handle_errors(returncode, result=None, args=args, kwargs=kwargs)
  File "etc/python/grass/script/core.py", line 429, in handle_errors
    raise CalledModuleError(module=module, code=code, returncode=returncode)
grass.exceptions.CalledModuleError: Module run `m.nviz.image elevation_map=elevation color_map=elevation output=/share/rkmeente/vpetras/tmp/grass8-vpetras-18913/tmpxbsais52/nviz format=tif size=600,400 mode=fine resolution_fine=1` ended with an error.
The subprocess ended with a non-zero return code: 1. See errors above the traceback or in the error output.

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ERROR: test_overlay (__main__.TestDisplay)
Check that overlay works
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Traceback (most recent call last):
  File "python/grass/jupyter/testsuite/test_render3d.py", line 107, in test_overlay
    renderer.render(elevation_map="elevation", color_map="elevation")
  File "etc/python/grass/jupyter/render3d.py", line 213, in render
    gs.run_command(module, env=env, **kwargs)
  File "etc/python/grass/script/core.py", line 541, in run_command
    return handle_errors(returncode, result=None, args=args, kwargs=kwargs)
  File "etc/python/grass/script/core.py", line 429, in handle_errors
    raise CalledModuleError(module=module, code=code, returncode=returncode)
grass.exceptions.CalledModuleError: Module run `m.nviz.image elevation_map=elevation color_map=elevation output=/share/rkmeente/vpetras/tmp/grass8-vpetras-18913/tmplsdvl486/nviz format=tif size=600,400 mode=fine resolution_fine=1` ended with an error.
The subprocess ended with a non-zero return code: 1. See errors above the traceback or in the error output.

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Ran 7 tests in 3.015s
FAILED (errors=5, skipped=1)
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FAILED ./python/grass/jupyter/testsuite/test_render3d.py (5 tests failed)