[Backport maintenance/3.2.x] Add prefer_stubs configuration

[github-actions]

Backport ee06feb from #2437.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

❗ No coverage uploaded for pull request base (maintenance/3.2.x@a7ff092). Click here to learn what that means.

Additional details and impacted files

@@                 Coverage Diff                  @@
##             maintenance/3.2.x    #2438   +/-   ##
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  Coverage                     ?   92.79%           
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  Files                        ?       94           
  Lines                        ?    11109           
  Branches                     ?        0           
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  Hits                         ?    10309           
  Misses                       ?      800           
  Partials                     ?        0           

Flag	Coverage Δ
linux	92.60% <88.23%> (?)
pypy	92.79% <100.00%> (?)
windows	92.69% <100.00%> (?)

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Files	Coverage Δ
astroid/interpreter/_import/spec.py	97.46% <100.00%> (ø)
astroid/manager.py	89.87% <100.00%> (ø)
astroid/modutils.py	88.19% <100.00%> (ø)