Create py.typed for use with mypy

[davidcavazos]

fixes #27906

Create type stub marker to allow mypy and other type checkers to run on user pipelines.

R: @aaltay @tvalentyn

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[codecov]

Codecov Report

Merging #27942 (32b3dbe) into master (a1ec055) will increase coverage by 0.00%.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master   #27942   +/-   ##
=======================================
  Coverage   72.23%   72.24%           
=======================================
  Files         684      684           
  Lines      100946   100961   +15     
=======================================
+ Hits        72921    72937   +16     
+ Misses      26445    26444    -1     
  Partials     1580     1580           

Flag	Coverage Δ
python	82.83% <ø> (+<0.01%)	⬆️

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[github-actions]

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R: @damccorm for label python.

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[tvalentyn]

Thanks, @davidcavazos . We need to include Apache licences in all files to pass RAT check.

[jrmccluskey]

The suggestion I dropped in should satisfy the RAT precommit

[tvalentyn]

this change didn't make the release cut unfortunately.

[davidcavazos]

It's currently under 2.50.0 Unreleased, I don't see a 2.51 so what should we do with this?

[damccorm]

If you pull in the changes from the master branch there is a 2.51 section - https://github.com/apache/beam/blob/master/CHANGES.md

[github-actions]

Reminder, please take a look at this pr: @damccorm

[davidcavazos]

The only open issue is where to announce the change in CHANGES.md, but I don't know where we should place it. Can someone point me in the right direction?

[damccorm]

If you pull in the changes from master (sync your fork then git pull origin master) you should be able to add it to the features/improvements section in the 2.51 section

[github-actions]

Reminder, please take a look at this pr: @damccorm

[davidcavazos]

Updated CHANGES for 2.51