Fix module dict in base finetuning

[ethanwharris]

What does this PR do?

Fixes #8169

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[codecov]

Codecov Report

Merging #8170 (7c25367) into master (c3065c5) will decrease coverage by 5%.
The diff coverage is 67%.

@@           Coverage Diff           @@
##           master   #8170    +/-   ##
=======================================
- Coverage      93%     88%    -5%     
=======================================
  Files         211     211            
  Lines       13440   13442     +2     
=======================================
- Hits        12450   11832   -618     
- Misses        990    1610   +620     

[tchaton]

LGTM !

[kaushikb11]

LGTM! Would suggest adding ModuleDict to the type hint for modules.