feat: gator test --deny-only flag

[WnP]

What this PR does / why we need it:

Add --deny-only flag to gator test command.

Which issue(s) this PR fixes:
Fixes #3808

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 84.21053% with 3 lines in your changes missing coverage. Please review.

Project coverage is 47.89%. Comparing base (3350319) to head (bd54b7b).
Report is 285 commits behind head on master.

Files with missing lines	Patch %	Lines
cmd/gator/test/test.go	84.21%	2 Missing and 1 partial ⚠️

❗ There is a different number of reports uploaded between BASE (3350319) and HEAD (bd54b7b). Click for more details.

HEAD has 1 upload less than BASE

Flag	BASE (3350319)	HEAD (bd54b7b)
unittests	2	1

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #3809      +/-   ##
==========================================
- Coverage   54.49%   47.89%   -6.61%     
==========================================
  Files         134      234     +100     
  Lines       12329    19881    +7552     
==========================================
+ Hits         6719     9522    +2803     
- Misses       5116     9470    +4354     
- Partials      494      889     +395     

Flag	Coverage Δ
unittests	47.89% <84.21%> (-6.61%)	⬇️

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[JaydipGabani]

lgtm, Thanks for the pr!

[WnP]

Thanks @JaydipGabani,
To easy the review I've rebased my feature branch so it's no longer marked "out of date".

[JaydipGabani]

@ritazh @sozercan PTAL

[ritazh]

Thanks for the PR @WnP ! can you pls add a note that this is only available after the v3.19 release. thanks!

[ritazh]

Suggested change

	The `--deny-only` will only output violations about denied constraints, not the ones using `warn` enforcement action.
	The `--deny-only` flag will only output violations about denied constraints, not the ones using `warn` enforcement action.

[ritazh]

LGTM
one nit

[JaydipGabani]

@WnP PTAL^^

[WnP]

Hi @JaydipGabani @ritazh,
Sorry for the delay I was quite busy lastly 🙏
Thanks for the review and merge :-)