Warn if a node_modules folder is included in content

[feelixe]

I think it would be a nice feature to output a warning to the console if you've added a glob pattern in content that includes any folder name node_modules. And the feature to disable this warning if it was your intention to include node_modules.
Why?

• It's easy to accidentally include a node_modules folder if you're new. Yes, the docs warn about this but in reality, not many will read that exact part before using.
• If you have a large project with a lot of packages then tailwind might fail during compile step because of too many files open. When this happened to me it took some time to figure out it was my config of content that caused it.
• Or, it does not fail which is almost as bad because it adds several minutes to your build time, with you potentially not knowing the reason.