Fix autosummary template

[flying-sheep]

The right way to do it is

.. currentmodule:: some_mod

.. autoclass:: SomeClass

   Methods table
   ~~~~~~~~~~~~~
   .. autosummary::
      SomeClass.some_method

instead of

.. currentmodule:: some_mod

.. autoclass:: SomeClass

   Methods table
   ~~~~~~~~~~~~~
   .. autosummary::
      some_mod.SomeClass.some_method

So the template needs to be changed:

 {% for item in methods %}
-    ~{{ fullname }}.{{ item }}
+    ~{{ name }}.{{ item }}
 {%- endfor %}

[github-actions]

A PR has been generated to the instance repo:
scverse/cookiecutter-scverse-instance#137

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