Resolving merge conflicts on files I'm told not to edit

What is the recommended method of resolving merge conflicts on files like yarn.lock and schema.rb -- both files I'm told not to edit. After running git merge jumpstart/master I have git merge conflict code to resolve, but it doesn't feel right to edit those files directly. This newbie would appreciate any guidance!

Generally for yarn.lock, Gemfile.lock, or any other package manager lock file, I've done this for years:

git checkout -- yarn.lock

yarn

git add yarn.lock

This resets the file to whatever was committed on your branch, and then running the package manager command will update the contents. I sometimes just delete the file and it seems to have the same affect.

For schema.rb I'm a Rails newbie too, not hit this yet. This seems reasonable: 

https://stackoverflow.com/a/7614339