Fix dataloaders are not reset when tuning the model

[Lucklyric]

What does this PR do?

Fixes #7562

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[codecov]

Codecov Report

Merging #7566 (92d8f31) into master (e126649) will decrease coverage by 4%.
The diff coverage is 100%.

@@           Coverage Diff           @@
##           master   #7566    +/-   ##
=======================================
- Coverage      92%     88%    -4%     
=======================================
  Files         196     198     +2     
  Lines       12835   12837     +2     
=======================================
- Hits        11854   11291   -563     
- Misses        981    1546   +565     

[carmocca]

Can you add a test that fails in current master and is fixed by the changes in this PR?

[tchaton]

LGTM ! Good catch ! Just need the tests.

[carmocca]

Added the test that fails in current master myself. LGTM

[carmocca]

Just noticed I'm not able to push changes to your fork's branch. I'm guessing you have disabled this:

https://docs.github.com/en/github/collaborating-with-issues-and-pull-requests/working-with-forks/allowing-changes-to-a-pull-request-branch-created-from-a-fork

Can you enable it? Alternatively, you can cherry-pick this commit d88b88c

[Lucklyric]

Dear @carmocca , it seems the option is already enabled. NVM, I have cherry-picked your revision. Thank you so much.

[ethanwharris]

LGTM 😃