test: fix testSendReceiveTwo and testBatchNack

[roseyang62]

Summary

This PR fixes flaky PubSub testSendReceiveTwo and testBatchNack conformance tests that were timing out in CI intermittently.

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1. add the module name as a prefix
   • for example: add a prefix: docstore: for document store module, blobstore for Blob Store module
2. for a test only PR, add test:
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[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 82.25%. Comparing base (03f6a8c) to head (4caf0fc).

Additional details and impacted files

@@             Coverage Diff              @@
##               main     #270      +/-   ##
============================================
- Coverage     82.36%   82.25%   -0.12%     
  Complexity      625      625              
============================================
  Files           191      191              
  Lines         11503    11503              
  Branches       1525     1525              
============================================
- Hits           9475     9462      -13     
- Misses         1357     1370      +13     
  Partials        671      671              

Flag	Coverage Δ
unittests	82.25% <ø> (-0.12%)	⬇️

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[sandeepvinayak]

Bringing WireMock into the test logic crosses the intended abstraction boundary. We should keep it only setup phase as in the current code and ensure the tests remain independent of the record/replay mechanism.

[sandeepvinayak]

this code breaks our design principle test shouldn't care/know if it's record/replay and is there is a wiremock in between.

[roseyang62]

Brief analysis of the root cause.

• Root Cause Analysis

The issue is related to how scenarios are handled in WireMock.
In AckMatcherRelaxingTransformer, we removed the scenario-related fields (scenarioName, requiredScenarioState, newScenarioState) from the stub mappings. As a result, the three pull stubs became unordered, independent stubs with identical request patterns. During replay, WireMock would match the same stub repeatedly, causing message duplication and out-of-order delivery.

• Current Status

After fixing, all recent CI runs have passed. I am not confident whether this fully resolves the underlying issue or simply reduces the likelihood of failure.
I have kept the additional debug print statements in the test. If the flakiness reappears in the future, it would indicate that this approach does not fully solve the problem and further investigation will be needed.