Refactor: switch to importlib.metadata.Distribution

[frostming]

Pull Request Check List

• A news fragment is added in news/ describing what is new.
• Test cases added for changed code.

Describe what you have changed in this PR.

[codecov-commenter]

Codecov Report

Merging #592 (5e452f2) into main (39189bb) will increase coverage by 0.00%.
The diff coverage is 84.12%.

@@           Coverage Diff           @@
##             main     #592   +/-   ##
=======================================
  Coverage   84.44%   84.44%           
=======================================
  Files          71       72    +1     
  Lines        5915     5935   +20     
  Branches     1044     1055   +11     
=======================================
+ Hits         4995     5012   +17     
+ Misses        640      635    -5     
- Partials      280      288    +8     

Flag	Coverage Δ
unittests	84.26% <83.33%> (-0.02%)	⬇️

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

Impacted Files	Coverage Δ
pdm/cli/commands/plugin.py	65.21% <50.00%> (ø)
pdm/installers/manager.py	85.71% <66.66%> (ø)
pdm/installers/uninstallers.py	83.41% <73.91%> (+0.08%)	⬆️
pdm/builders/base.py	91.78% <83.33%> (+0.05%)	⬆️
pdm/cli/utils.py	82.69% <84.21%> (-0.46%)	⬇️
pdm/models/working_set.py	84.44% <84.44%> (ø)
pdm/_types.py	100.00% <100.00%> (ø)
pdm/cli/actions.py	75.64% <100.00%> (-0.16%)	⬇️
pdm/installers/synchronizers.py	84.50% <100.00%> (+0.14%)	⬆️
pdm/models/environment.py	71.05% <100.00%> (-4.98%)	⬇️
... and 5 more

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