Removing yaml extension from hydra config names in defaults lists.

[tesfaldet]

What does this PR do?

Fixes #420.

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👍

[tesfaldet]

Tests can be fixed from this PR #585

[codecov-commenter]

Codecov Report

Patch and project coverage have no change.

Comparison is base (9355a5d) 83.66% compared to head (b86feb5) 83.66%.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #584   +/-   ##
=======================================
  Coverage   83.66%   83.66%           
=======================================
  Files          11       11           
  Lines         355      355           
=======================================
  Hits          297      297           
  Misses         58       58           

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[ashleve]

Thanks for taking care of this ❤️