VStreamer unit tests: Port more tests to new framework

[rohit-nayak-ps]

Description

Migrates more tests from vstreamer_test.go to the new framework from https://github.com/vitessio/vitess/pull/14903 and enhanced the framework as needed.

Related Issue(s)

https://github.com/vitessio/vitess/pull/14903

Checklist

• [ ] "Backport to:" labels have been added if this change should be back-ported to release branches
• [ ] If this change is to be back-ported to previous releases, a justification is included in the PR description
• [ ] Tests were added or are not required
• [ ] Did the new or modified tests pass consistently locally and on CI?
• [ ] Documentation was added or is not required

[vitess-bot[bot]]

Review Checklist

Hello reviewers! :wave: Please follow this checklist when reviewing this Pull Request.

General

• [ ] Ensure that the Pull Request has a descriptive title.
• [ ] Ensure there is a link to an issue (except for internal cleanup and flaky test fixes), new features should have an RFC that documents use cases and test cases.

Tests

• [ ] Bug fixes should have at least one unit or end-to-end test, enhancement and new features should have a sufficient number of tests.

Documentation

• [ ] Apply the release notes (needs details) label if users need to know about this change.
• [ ] New features should be documented.
• [ ] There should be some code comments as to why things are implemented the way they are.
• [ ] There should be a comment at the top of each new or modified test to explain what the test does.

New flags

• [ ] Is this flag really necessary?
• [ ] Flag names must be clear and intuitive, use dashes (-), and have a clear help text.

If a workflow is added or modified:

• [ ] Each item in Jobs should be named in order to mark it as required.
• [ ] If the workflow needs to be marked as required, the maintainer team must be notified.

Backward compatibility

• [ ] Protobuf changes should be wire-compatible.
• [ ] Changes to _vt tables and RPCs need to be backward compatible.
• [ ] RPC changes should be compatible with vitess-operator
• [ ] If a flag is removed, then it should also be removed from vitess-operator and arewefastyet, if used there.
• [ ] vtctl command output order should be stable and awk-able.

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 67.63%. Comparing base (27be916) to head (e48b201). Report is 14 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #15287      +/-   ##
==========================================
+ Coverage   67.53%   67.63%   +0.09%     
==========================================
  Files        1561     1561              
  Lines      193387   193525     +138     
==========================================
+ Hits       130607   130885     +278     
+ Misses      62780    62640     -140     

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[rohit-nayak-ps]

Since there are no reviews yet, closing this in favor of https://github.com/vitessio/vitess/pull/15366 which aims to port all the tests in vstreamer_test.go.