Disallow invalid seed string values

[stancld]

What does this PR do?

See title.
Fixes mypy typing in utilities.seed.py

Part of #7037. This PR disentangles large #7218

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

Passing invalid seed values to seed_everything is now disallowed.

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[codecov]

Codecov Report

Merging #8787 (d7f616a) into master (530caef) will increase coverage by 1%.
The diff coverage is 100%.

❗ Current head d7f616a differs from pull request most recent head 0994577. Consider uploading reports for the commit 0994577 to get more accurate results

@@           Coverage Diff            @@
##           master   #8787     +/-   ##
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+ Coverage      88%     89%     +1%     
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  Files         178     179      +1     
  Lines       14889   19134   +4245     
========================================
+ Hits        13122   17120   +3998     
- Misses       1767    2014    +247     

[tchaton]

Dear @stancld,

Any updates on this PR ?

Best,
T.C

[stancld]

Dear @tchaton: @awaelchli stressed the importance to keep the functionality the same. In this case, however, satisfying the requirements imposed by mypy leads to much more complex code. Since here, the possible type errors are handled by try - except statement, would it be possible just to ask mypy not to check the typing for the line stating seed = int(seed)?

[awaelchli]

Yes I think we should favor reproducibility here and not the typing. Let's not change the implementation unless there is a bug. In this case ignoring a line there for mypy is well justified imo

[tchaton]

Dear @awaelchli @stancld,

First of all, thanks @stancld for investing time and effort on this PR. This is well appreciated !
What should we do ? Close this PR or add ignore flags for mypy there with a comment on why we made this decision ?

Best.
T.C

[stancld]

@tchaton If it's okay I would re-write this PR tomorrow and add two ignoring comments with a supplementary one why this solution is appropriate :)

[tchaton]

Hey @stancld,

Thanks for helping out !

Best,
T.C

[tchaton]

LGTM !