[WIP] Fix mypy typing for utilities.auto_restart

[stancld]

What does this PR do?

Part of #7037. This PR disentangles large #7218. It fixes mypy typing in utilities.auto_restart.py

There's one last tough mypy issue:

torch_lightning/utilities/auto_restart.py:86: error: Argument 1 to "len" has incompatible type "Union[Sampler[Any], Generator[Any, Any, Any], Iterator[Any]]"; expected "Sized"  [arg-type]

Does your PR introduce any breaking changes? If yes, please list them.

None

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[codecov]

Codecov Report

Merging #8783 (60f12e3) into master (f1cc6e3) will decrease coverage by 4%.
The diff coverage is 90%.

@@           Coverage Diff           @@
##           master   #8783    +/-   ##
=======================================
- Coverage      93%     88%    -4%     
=======================================
  Files         169     169            
  Lines       14068   14075     +7     
=======================================
- Hits        13038   12452   -586     
- Misses       1030    1623   +593     

[carmocca]

pretty sure this is not necessary :/

[awaelchli]

do you think we should we put warn_no_return = False for mypy? @stancld @carmocca

[stancld]

I remember I read a PEP recommendation suggesting if there's any return statement within a function, it should be obeyed for the whole function definition. But yes, my suggestion might be redundant here.

[stale]

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[stale]

This pull request is going to be closed. Please feel free to reopen it create a new from the actual master.