[Bugfix] Detach Loaders after running entrypoint

[justusschock]

What does this PR do?

Fixes #8868

Restores the original dataloaders after the entrypoint if replaced during the run.

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

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[codecov]

Codecov Report

Merging #8885 (a1753ab) into master (4b6aaee) will increase coverage by 0%.
The diff coverage is 100%.

@@          Coverage Diff           @@
##           master   #8885   +/-   ##
======================================
  Coverage      93%     93%           
======================================
  Files         169     169           
  Lines       14079   14098   +19     
======================================
+ Hits        13053   13072   +19     
  Misses       1026    1026           

[justusschock]

@ananthsub This is a short-term fix for the issue, which still does not resolve #6030 .

However, I think we should do this in a separate PR after discussion on how we do it instead, which is why I sent this fix :)