Chore: set minimal python version to 3.10

[Guts]

Since some advanced types operations introduced in mkdocs>=1.5 are not entirely supported by Python 3.8 and 3.9, let's switch to 3.10 as minimal version:

Logs with failing error in #285 (https://github.com/Guts/mkdocs-rss-plugin/actions/runs/9450849461/job/26030426819?pr=285):

FAILED tests/test_build.py::TestBuildRss::test_simple_build_custom_output_basename - TypeError: Subscripted generics cannot be used with class and instance checks

/opt/hostedtoolcache/Python/3.8.18/x64/lib/python3.8/site-packages/mkdocs/plugins.py:96: in load_config
    return self.config.validate()
/opt/hostedtoolcache/Python/3.8.18/x64/lib/python3.8/site-packages/mkdocs/config/base.py:231: in validate
    run_failed, run_warnings = self._validate()
/opt/hostedtoolcache/Python/3.8.18/x64/lib/python3.8/site-packages/mkdocs/config/base.py:188: in _validate
    self[key] = config_option.validate(value)
/opt/hostedtoolcache/Python/3.8.18/x64/lib/python3.8/site-packages/mkdocs/config/base.py:55: in validate
    return self.run_validation(value)
/opt/hostedtoolcache/Python/3.8.18/x64/lib/python3.8/site-packages/mkdocs/config/config_options.py:110: in run_validation
    failed, warnings = config.validate()
/opt/hostedtoolcache/Python/3.8.18/x64/lib/python3.8/site-packages/mkdocs/config/base.py:231: in validate
    run_failed, run_warnings = self._validate()
/opt/hostedtoolcache/Python/3.8.18/x64/lib/python3.8/site-packages/mkdocs/config/base.py:188: in _validate
    self[key] = config_option.validate(value)
/opt/hostedtoolcache/Python/3.8.18/x64/lib/python3.8/site-packages/mkdocs/config/config_options.py:186: in validate
    return self.run_validation(value)
/opt/hostedtoolcache/Python/3.8.18/x64/lib/python3.8/site-packages/mkdocs/config/config_options.py:344: in run_validation
    if not isinstance(value, self._type):
/opt/hostedtoolcache/Python/3.8.18/x64/lib/python3.8/typing.py:769: in __instancecheck__
    return self.__subclasscheck__(type(obj))
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

[sonarqubecloud]

Quality Gate passed

Issues
1 New issue
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
0.0% Duplication on New Code

See analysis details on SonarCloud

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 83.12%. Comparing base (1f4f792) to head (8ec6164).
Report is 6 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #286      +/-   ##
==========================================
- Coverage   85.04%   83.12%   -1.93%     
==========================================
  Files          10       10              
  Lines         555      551       -4     
  Branches      117      116       -1     
==========================================
- Hits          472      458      -14     
- Misses         53       64      +11     
+ Partials       30       29       -1     

Flag	Coverage Δ
unittests	83.12% <100.00%> (-1.75%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files	Coverage Δ
...lugin/integrations/theme_material_social_plugin.py	96.87% <ø> (-0.05%)	⬇️
mkdocs_rss_plugin/models.py	100.00% <100.00%> (ø)
mkdocs_rss_plugin/plugin.py	94.02% <100.00%> (-0.05%)	⬇️
mkdocs_rss_plugin/util.py	75.00% <100.00%> (-0.21%)	⬇️

... and 1 file with indirect coverage changes