[BEAM-13081] Elide null bytes when encoding in Python RowCoder

[TheNeuralBit]

Also add a test case to standard_coders.yaml

ValidatesRunner compliance status (on master branch)

Lang	ULR	Dataflow	Flink	Samza	Spark	Twister2
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Java
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XLang						---

Examples testing status on various runners

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Post-Commit SDK/Transform Integration Tests Status (on master branch)

Go	Java	Python

Pre-Commit Tests Status (on master branch)

---	Java	Python	Go	Website	Whitespace	Typescript
Non-portable
Portable	---			---	---	---

See .test-infra/jenkins/README for trigger phrase, status and link of all Jenkins jobs.

GitHub Actions Tests Status (on master branch)

See CI.md for more information about GitHub Actions CI.

[TheNeuralBit]

R: @steveniemitz

[codecov]

Codecov Report

Merging #15938 (f45c714) into master (03d4e42) will decrease coverage by 0.00%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master   #15938      +/-   ##
==========================================
- Coverage   83.53%   83.53%   -0.01%     
==========================================
  Files         445      445              
  Lines       61385    61387       +2     
==========================================
- Hits        51279    51277       -2     
- Misses      10106    10110       +4     

Impacted Files	Coverage Δ
sdks/python/apache_beam/internal/metrics/metric.py	90.00% <0.00%> (-1.00%)	⬇️
...hon/apache_beam/runners/worker/bundle_processor.py	93.26% <0.00%> (-0.38%)	⬇️
sdks/python/apache_beam/coders/row_coder.py	95.13% <0.00%> (+0.06%)	⬆️

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[github-actions]

This pull request has been marked as stale due to 60 days of inactivity. It will be closed in 1 week if no further activity occurs. If you think that’s incorrect or this pull request requires a review, please simply write any comment. If closed, you can revive the PR at any time and @mention a reviewer or discuss it on the dev@beam.apache.org list. Thank you for your contributions.

[TheNeuralBit]

I'm working on syncing this up. The conflicting change is the RowCoder refactor, so resolving the conflict is non-trivial.

[github-actions]

This pull request has been marked as stale due to 60 days of inactivity. It will be closed in 1 week if no further activity occurs. If you think that’s incorrect or this pull request requires a review, please simply write any comment. If closed, you can revive the PR at any time and @mention a reviewer or discuss it on the dev@beam.apache.org list. Thank you for your contributions.

[github-actions]

This pull request has been closed due to lack of activity. If you think that is incorrect, or the pull request requires review, you can revive the PR at any time.