Exclude tests

[TrevorBurnham]

First off, great work on this plugin! It's a lifesaver.

One suggestion: Currently, the plugin seems to want to add 'use client' to the top of every test file that uses JSX. Of course, users could configure ESLint to only apply the plugin to non-test files, but that can be tricky. It'd be great if there was some heuristic that the plugin could use to determine what's a test and what isn't. As a first approximation, I think you could safely ignore all files that don't have any exports.

[roginfarrer]

Thanks! Glad that it has proved useful.

I don't think we can accurately validate whether a file is a test file or not without hardcoding conventions, which can change overtime and can vary between codebases. Maybe we should add something to the readme to specify that it should be used in overrides? (where you can include/exclude the files you want the rules to apply to).

I'm also pretty sure we cannot safely ignore files without exports. For example, you might have a simple express server that uses renderToString, and those files don't always have exports.