Tests: Add test in syslogger for LOG_EMERG level

[rajivharlalka]

Description

Add missing check for the LOG_EMERG logging level in syslogger.

Related Issue(s)

Part of #14931

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

Deployment Notes

[vitess-bot]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (9552e4c) 47.25% compared to head (0db4a37) 47.25%.
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #14942   +/-   ##
=======================================
  Coverage   47.25%   47.25%           
=======================================
  Files        1138     1138           
  Lines      238842   238842           
=======================================
+ Hits       112867   112874    +7     
+ Misses     117372   117364    -8     
- Partials     8603     8604    +1     

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[mattlord]

Thank you, @rajivharlalka !

We can see that the code coverage for syslogger.go went from 89.71% on main to 94.12% in the PR branch:

• https://app.codecov.io/gh/vitessio/vitess/tree/main/go%2Fevent%2Fsyslogger
• https://app.codecov.io/gh/vitessio/vitess/pull/14942/tree/go/event/syslogger

[frouioui]

Looks great to me!

[rajivharlalka]

Thanks @mattlord @frouioui , I hope that syslog doesn't need more tests as I could not find a way to increase the test coverage to 100% for the remaining part? Would be eager to understand if that was possible and would surely do it.