test(resource-name): generate code for resource name heuristics demo

[haphungw]

Regenerate all client libraries via librarian generate --all.
We've enabled generating resource_name via the resource_name: true toggle in librarian.yaml for APIs that were previously missing resource names or generating incorrect strings.

• google-cloud-dns-v1
• google-cloud-build-v1
• google-cloud-secret-manager-v1
• google-cloud-api-keys-v2
• showcase-v1beta1

Depends on:

1. feat(sidekick/rust): decouple option extraction and support resource names (roll-forward) librarian#4385
2. fix(rust): skip version prefix from generated resource names librarian#4474
3. feat(sidekick): remove heuristic eligibleServices allowlist librarian#4469
4. fix(internal/sidekick): crop trailing literals from resource names librarian#4488

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 93.95%. Comparing base (15d5fce) to head (b9232c7).
⚠️ Report is 4 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4936      +/-   ##
==========================================
+ Coverage   93.94%   93.95%   +0.01%     
==========================================
  Files         221      221              
  Lines        8538     8538              
==========================================
+ Hits         8021     8022       +1     
+ Misses        517      516       -1     

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