Enable SyncBatchNorm For LightningLite

[lsy643]

What does this PR do?

Fixes https://github.com/Lightning-AI/lightning/issues/13749

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

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[codecov[bot]]

Codecov Report

Merging #13748 (0637e36) into master (c67b075) will decrease coverage by 10%. The diff coverage is n/a.

@@            Coverage Diff            @@
##           master   #13748     +/-   ##
=========================================
- Coverage      86%      76%    -10%     
=========================================
  Files         327      327             
  Lines       25432    25432             
=========================================
- Hits        21862    19342   -2520     
- Misses       3570     6090   +2520     

[lsy643]

LGTM ! Mind adding a test ?

Sure. I was stuck by something else in the past weeks, and I will add it soon

[Borda]

@awaelchli, mind checking this one? :otter:

[awaelchli]

@Borda I replied already on the linked issue https://github.com/Lightning-AI/lightning/issues/13749#issuecomment-1250146805

[carmocca]

@lsy643 Thanks for your contribution. This is blocked by other larger pieces of work so we should revisit this after we can do it. Closing for now, let's continue discussing in the linked issue.