Update actions/checkout action to v4

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
actions/checkout	action	major	v3 -> v4

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Release Notes

actions/checkout (actions/checkout)

v4

Compare Source

• Bump the minor-npm-dependencies group across 1 directory with 4 updates by @​dependabot in https://github.com/actions/checkout/pull/1739
• Bump actions/checkout from 3 to 4 by @​dependabot in https://github.com/actions/checkout/pull/1697
• Check out other refs/* by commit by @​orhantoy in https://github.com/actions/checkout/pull/1774
• Pin actions/checkout's own workflows to a known, good, stable version. by @​jww3 in https://github.com/actions/checkout/pull/1776

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Configuration

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[github-actions]

Test coverage for b49b1bc

Name                                            Stmts   Miss Branch BrPart  Cover   Missing
-------------------------------------------------------------------------------------------
paas_app_charmer/__init__.py                       32     17      0      0    47%   13-14, 19-20, 26-27, 33-37, 43-44, 50-51, 57-58
paas_app_charmer/_gunicorn/__init__.py              0      0      0      0   100%
paas_app_charmer/_gunicorn/charm.py                15      0      0      0   100%
paas_app_charmer/_gunicorn/webserver.py            83      4     14      1    95%   175, 187-193
paas_app_charmer/_gunicorn/workload_config.py       8      0      0      0   100%
paas_app_charmer/_gunicorn/wsgi_app.py             16      0      0      0   100%
paas_app_charmer/app.py                           157      0     54      3    99%   110->exit, 167->173, 341->343
paas_app_charmer/charm.py                         242     26     54      3    90%   34-35, 42-43, 205, 215-216, 218-219, 248-252, 316-318, 379-380, 385, 390, 395, 405, 410, 415, 420, 425, 450
paas_app_charmer/charm_state.py                   107      2     12      2    97%   187, 277
paas_app_charmer/charm_utils.py                    23      0      0      0   100%
paas_app_charmer/database_migration.py             35      0      2      0   100%
paas_app_charmer/databases.py                      25      2      6      1    90%   89-90
paas_app_charmer/django/__init__.py                 2      0      0      0   100%
paas_app_charmer/django/charm.py                   44      4      8      2    88%   48, 108, 123-124
paas_app_charmer/exceptions.py                      5      0      0      0   100%
paas_app_charmer/fastapi/__init__.py                2      0      0      0   100%
paas_app_charmer/fastapi/charm.py                  31      0      0      0   100%
paas_app_charmer/flask/__init__.py                  2      0      0      0   100%
paas_app_charmer/flask/charm.py                    26      0      0      0   100%
paas_app_charmer/framework.py                      23      4     12      2    77%   34, 47-49
paas_app_charmer/go/__init__.py                     2      0      0      0   100%
paas_app_charmer/go/charm.py                       28      0      0      0   100%
paas_app_charmer/observability.py                  24      3      4      1    86%   42->46, 73-77
paas_app_charmer/rabbitmq.py                       78      2     22      5    93%   117->exit, 122->exit, 157->exit, 159-160, 181->175
paas_app_charmer/secret_storage.py                 50      2     14      4    91%   55->54, 56->58, 86, 105
paas_app_charmer/utils.py                          44      7     14      5    79%   34, 36, 56-57, 75, 79, 104
-------------------------------------------------------------------------------------------
TOTAL                                            1104     73    216     29    92%

Static code analysis report

Run started:2024-10-11 16:13:48.195975

Test results:
  No issues identified.

Code scanned:
  Total lines of code: 2368
  Total lines skipped (#nosec): 1
  Total potential issues skipped due to specifically being disabled (e.g., #nosec BXXX): 2

Run metrics:
  Total issues (by severity):
  	Undefined: 0
  	Low: 0
  	Medium: 0
  	High: 0
  Total issues (by confidence):
  	Undefined: 0
  	Low: 0
  	Medium: 0
  	High: 0
Files skipped (0):