Ignore node_modules by default

[devjiwonchoi]

Background

When setting the content field of tailwind.config.ts, we often miss out that the node_modules can be included:

export default {
  content: ['./**/*.{ts,tsx}'],
}

Which could cause the app to handle unnecessary files.

Proposal

Ignore the node_modules by default unless explicitly set the path.

I am willing to contribute.