If you clone a git repo that enforces a linebreak-style: unix on a Windows machine then ESLint will probably throw the warning below even if you've made no local changes.
Expected linebreaks to be LF but found CRLF. linebreak-style
In order to fix this you'll need to tell git to default to Unix style line endings rather that OS defaults.
git config --global core.eol lf
git config --global core.autocrlf input
Finally remember to save your work and then reset the repo so the new line endings get applied.
git rm -rf --cached .
git reset HEAD --hard
it works! :)