feat(github-comments): Don't comment info-level issues on merged PRs

[iamrajjoshi]

• Added additional filter to prevent comments for info level issues on merged issues.
• Prevented the trigger of the comment workflow
• Added additional expression in the WHERE clause of snuba query
• Wrote tests for both changes

Fixes: https://github.com/getsentry/team-core-product-foundations/issues/126

[cathteng]

looks good, just some nits

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 84.26%. Comparing base (3c45415) to head (b09469e).
Report is 19 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff            @@
##           master   #66110    +/-   ##
========================================
  Coverage   84.25%   84.26%            
========================================
  Files        5293     5294     +1     
  Lines      236792   236917   +125     
  Branches    41007    41030    +23     
========================================
+ Hits       199513   199627   +114     
- Misses      37060    37071    +11     
  Partials      219      219            

Files	Coverage Δ
src/sentry/tasks/commit_context.py	99.18% <100.00%> (+0.01%)	⬆️
src/sentry/tasks/integrations/github/pr_comment.py	100.00% <ø> (ø)

... and 18 files with indirect coverage changes

[cathteng]

🚀