[No QA] Continue merge without requiring editor

[roryabraham]

Details

In the local testing of #9771 the editor was required to finish the merge commit. I thought that this wouldn't happen in the GH runner because they have pager disabled by default, but I was wrong. This PR makes it so that, even testing locally, the editor is not required to finish the merge commit.

Fixed Issues

$ n/a – broken deploys.

Local Tests

1. Go to the App repo locally and run these commands:

   git fetch
   git checkout main
   git checkout -b fake-main
   git checkout main
   git checkout -b fake-staging
   echo "Update README on staging" >> README.md
   git add README.md
   git commit -m "Update README on staging"
   git checkout fake-main
   rm README.md
   git add README.md
   git commit -m "Delete README on main"
   git checkout fake-staging
   git merge -Xtheirs fake-main || {
     git diff --name-only --diff-filter=U | xargs git rm;  
     git merge -c core.editor=true --continue;
   }

2. Verify that the merge in the last command succeeds and that it DOES NOT open an editor and prompt you for a commit message.

Live Tests

1. Merge this PR
2. RE-ship Deploy Checklist: New Expensify 2022-06-28 #9586 and the deploy should work.

[luacmartins]

LGTM and tests well!

[OSBotify]

🚀 Deployed to staging by @roryabraham in version: 1.1.81-0 🚀

platform	result
🤖 android 🤖	failure ❌
🖥 desktop 🖥	success ✅
🍎 iOS 🍎	success ✅
🕸 web 🕸	failure ❌

[OSBotify]

🚀 Deployed to production by @roryabraham in version: 1.1.82-5 🚀

platform	result
🤖 android 🤖	success ✅
🖥 desktop 🖥	success ✅
🍎 iOS 🍎	failure ❌
🕸 web 🕸	success ✅