CompatHelper: bump compat for MLDatasets to 0.6 for package nmf, (keep existing compat)

[github-actions]

This pull request changes the compat entry for the MLDatasets package from 0.5 to 0.5, 0.6 for package nmf.
This keeps the compat entries for earlier versions.

Note: I have not tested your package with this new compat entry.
It is your responsibility to make sure that your package tests pass before you merge this pull request.

[coveralls]

Pull Request Test Coverage Report for Build 2284723176

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

• For more information on this, see Tracking coverage changes with pull request builds.
• To avoid this issue with future PRs, see these Recommended CI Configurations.
• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 95.426%

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Totals
Change from base Build 1768612297:	0.0%
Covered Lines:	605
Relevant Lines:	634

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💛 - Coveralls

[codecov-commenter]

Codecov Report

Merging #166 (e082557) into master (a82e3fb) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #166   +/-   ##
=======================================
  Coverage   95.42%   95.42%           
=======================================
  Files          14       14           
  Lines         634      634           
=======================================
  Hits          605      605           
  Misses         29       29           

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