Filter in-app frames to decide for CODEOWNERS

[alxckn]

Fixes #57828 ?

I believe the assignment rules may in fact process the entire stack trace instead of simply the in-app frames.

Legal Boilerplate

Look, I get it. The entity doing business as "Sentry" was incorporated in the State of Delaware in 2015 as Functional Software, Inc. and is gonna need some rights from me in order to utilize my contributions in this here PR. So here's the deal: I retain all rights, title and interest in and to my contributions, and by keeping this boilerplate intact I confirm that Sentry can use, modify, copy, and redistribute my contributions, under Sentry's choice of terms.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 84.31%. Comparing base (7d5ee4b) to head (fb4f2ae).
Report is 1368 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #67908      +/-   ##
==========================================
- Coverage   84.34%   84.31%   -0.03%     
==========================================
  Files        5314     5322       +8     
  Lines      237352   237819     +467     
  Branches    41050    41131      +81     
==========================================
+ Hits       200184   200512     +328     
- Misses      36950    37089     +139     
  Partials      218      218              

Files	Coverage Δ
src/sentry/ownership/grammar.py	94.07% <100.00%> (-4.88%)	⬇️

... and 250 files with indirect coverage changes

[getsantry]

This pull request has gone three weeks without activity. In another week, I will close it.

But! If you comment or otherwise update it, I will reset the clock, and if you add the label WIP, I will leave it alone unless WIP is removed ... forever!

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"A weed is but an unloved flower." ― Ella Wheeler Wilcox 🥀