Dependabot suggestion to edit yarn.lock results in Rails server refusing to work, saying to run `yarn install --check-files`

Question

I have a Rails application, and Dependabot says:

When I modify the yarn.lock file as per that suggestion, and try to run rails s, I get this:

warning Integrity check: Lock files don't match
error Integrity check failed
error Found 1 errors.

========================================
  Your Yarn packages are out of date!
  Please run `yarn install --check-files` to update.
========================================

When I run yarn install --check-files, my modification is overwritten with the original old offending version.

What should I do?