fix: correct and simplify git push/pull request classification using content-type headers

[kriswest]

resolves: #1185

SIimple PR that replaces the existing checks in parseAction with a simpler test based on the content-type headers which should be both correct (the previous check for a GET request was not - pulls were being misclassified as default actions) and simpler to comprehend.

[netlify]

✅ Deploy Preview for endearing-brigadeiros-63f9d0 canceled.

Name	Link
🔨 Latest commit	1312a6e
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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 83.46%. Comparing base (375bd13) to head (1312a6e).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1249      +/-   ##
==========================================
+ Coverage   83.40%   83.46%   +0.05%     
==========================================
  Files          70       70              
  Lines        3007     3005       -2     
  Branches      501      499       -2     
==========================================
  Hits         2508     2508              
+ Misses        396      394       -2     
  Partials      103      103              

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[JamieSlome]

LGTM! 🍰

[06kellyjac]

@JamieSlome good to see you here 🚀 I hope you're doing well.
Would you be able to update your LFX EasyCLA setup? After merging in main it's blocked for merging