[yaml] move pipeline examples from blueprint to pipelines

[derrickaw]

1. [yaml] switch blueprint to pipelines #40545 was merged a few days ago, but a few new pipeline examples came in afterwards that didn't redirect them to the new pipelines folder.
2. Just shifting the examples to a different folder.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 79.88%. Comparing base (76f6e6d) to head (c305d6c).
⚠️ Report is 194 commits behind head on master.

Additional details and impacted files

@@              Coverage Diff              @@
##             master   #40615       +/-   ##
=============================================
+ Coverage     56.16%   79.88%   +23.71%     
=============================================
  Files          1124      488      -636     
  Lines        178336    82431    -95905     
  Branches       1489        0     -1489     
=============================================
- Hits         100170    65846    -34324     
+ Misses        75645    16585    -59060     
+ Partials       2521        0     -2521     

Flag	Coverage Δ
go	?
java	?
python	79.88% <ø> (+0.32%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Harness.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[derrickaw]

/gemini review

[github-actions]

📋 Review Summary

This PR moves the remaining two YAML example files (bigquery_to_bigtable.yaml and gcs_avro_to_cloud_bigtable.yaml) from sdks/python/apache_beam/yaml/examples/transforms/blueprint/ to sdks/python/apache_beam/yaml/examples/transforms/pipelines/, completing the directory rename initiated in PR #40545. The change is clean and also restores test discovery for both examples under PipelinesTest in sdks/python/apache_beam/yaml/examples/testing/examples_test.py.

🔍 General Feedback

• No remaining files or references to transforms/blueprint exist in the repository.
• Both test_bigquery_to_bigtable_yaml and test_gcs_avro_to_cloud_bigtable_yaml are already registered in examples_test.py preprocessors and will now be properly discovered and executed by PipelinesTest.

---

💡 Tip: Comment /gemini review on this pull request to trigger a new Gemini code review.

[github-actions]

Assigning reviewers:

R: @chamikaramj for label yaml.
Backup reviewer: Abacn (if the main reviewer is unresponsive, you can escalate to them by tagging their username)

Note: If you would like to opt out of this review, comment assign to next reviewer.

Available commands:

• stop reviewer notifications - opt out of the automated review tooling
• remind me after tests pass - tag the comment author after tests pass
• waiting on author - shift the attention set back to the author (any comment or push by the author will return the attention set to the reviewers)

The PR bot will only process comments in the main thread (not review comments).