Add internal yarn files to .gitignore #5983
Description
In #5960, @ayushrai206 added files such as main/tests/cypress/.yarn/cache/@babel-helper-string-parser-npm-7.22.5-448ff0e489-836851ca5e.zip to some commits by mistake.
On my machine, yarn does not seem to create those .yarn directories but it feels like they should be added to our .gitignore file(s) to prevent that. The same goes for .yarnrc.yml.