Fix Deepspeed and lightning calling scheduler

[SeanNaren]

What does this PR do?

Fixes #9771

After speaking to @tchaton we decided to remove the scheduler responsibility from DeepSpeed, fully relying on Lightning to control when to call the lr scheduler step function. This also allows users to use epoch vs step calls which is not possible in DeepSpeed.

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[tchaton]

LGMT !

[codecov]

Codecov Report

Merging #9788 (43a910a) into master (9d98208) will increase coverage by 0%.
The diff coverage is 100%.

@@          Coverage Diff           @@
##           master   #9788   +/-   ##
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  Coverage      93%     93%           
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  Files         177     177           
  Lines       15460   15465    +5     
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+ Hits        14323   14328    +5     
  Misses       1137    1137