Reverting few changes

[WenkelF]

Changelogs

• Avoid removing dirpath from config as used for saving checkpoint to wandb
• Setting mlp_expansion_ration from 4 back to 2

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Checklist:

• [ ] Was this PR discussed in an issue? It is recommended to first discuss a new feature into a GitHub issue before opening a PR.
• [ ] Add tests to cover the fixed bug(s) or the new introduced feature(s) (if appropriate).
• [ ] Update the API documentation is a new function is added, or an existing one is deleted.
• [ ] Write concise and explanatory changelogs above.
• [ ] If possible, assign one of the following labels to the PR: feature, fix or test (or ask a maintainer to do it for you).

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discussion related to that PR

[codecov[bot]]

Codecov Report

Merging #484 (3f2b799) into main (e5fa686) will not change coverage. The diff coverage is 100.00%.

@@           Coverage Diff           @@
##             main     #484   +/-   ##
=======================================
  Coverage   71.41%   71.41%           
=======================================
  Files          93       93           
  Lines        8525     8525           
=======================================
  Hits         6088     6088           
  Misses       2437     2437           

Flag	Coverage Δ
unittests	71.41% <100.00%> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
ipu	49.14% <ø> (ø)

[DomInvivo]

@kerstink-GC , can you check this PR?

[DomInvivo]

Please make sure that the change in default value is well documented