binarylog: replace testServer with StubServer in binarylog_end2end_test.go

[110y]

• binarylog: replace testServer with StubServer in binarylog_end2end_test.go
  • stubserver: add support to optionally pass in a grpc.Server or xds.GRPCServer #7291

RELEASE NOTES: none

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 82.97%. Comparing base (36e13de) to head (d212ea6).
⚠️ Report is 3 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #8978      +/-   ##
==========================================
- Coverage   83.01%   82.97%   -0.05%     
==========================================
  Files         411      411              
  Lines       32719    32892     +173     
==========================================
+ Hits        27162    27291     +129     
- Misses       4167     4200      +33     
- Partials     1390     1401      +11     

see 34 files with indirect coverage changes

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[easwars]

While you are here, would you mind changing the clientconn method on test and instead do the following:

• In test.startServer call stubserver.Start() instead of StartServer()
  • This would also end up creating a ClientConn to the newly created stub server
• In test.clientconn, return stubserver.CC
• Or optionally, get rid of this test.clientconn method and directly use test.ss.CC if possible.
• Either way is fine

[110y]

👍
I got rid of test.clientConn (and test.tearDown): d212ea6