Add counter for MLTransform and data processing transforms

[AnandInguva]

Adds counters to the MLTransform and data processing transforms.

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[codecov]

Codecov Report

Merging #28927 (c064082) into master (e130352) will decrease coverage by 0.02%.
Report is 8 commits behind head on master.
The diff coverage is 26.31%.

@@            Coverage Diff             @@
##           master   #28927      +/-   ##
==========================================
- Coverage   72.16%   72.15%   -0.02%     
==========================================
  Files         686      686              
  Lines      101554   101573      +19     
==========================================
+ Hits        73291    73292       +1     
- Misses      26684    26702      +18     
  Partials     1579     1579              

Flag	Coverage Δ
python	82.59% <26.31%> (-0.03%)	⬇️

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Files	Coverage Δ
sdks/python/apache_beam/ml/transforms/base.py	49.38% <26.31%> (-7.07%)	⬇️

... and 4 files with indirect coverage changes

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[riteshghorse]

Run Portable_Python PreCommit

[riteshghorse]

LGTM, thanks!

[riteshghorse]

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