CSS codemod: do not wrap comment nodes in @layer

[RobinMalfait]

When CSS exists between two tailwind directives, then the CSS will be wrapped in an @layer to ensure it all ends up in the correct location in the final CSS file.

However, if the only thing between two tailwind directives is a comment, then the comment will also be wrapped in an @layer directive.

E.g.:

@tailwind base;
/* This is a comment */
@tailwind components;
/* This is another comment */
@tailwind utilities;

Results in:

@import "tailwindcss";
@layer base {
  /* This is a comment */
}
@layer components {
  /* This is another comment */
}

In this case, the layers don't matter, so this can be simplified to:

@import "tailwindcss";
/* This is a comment */
/* This is another comment */

[philipp-spiess]

Niceeee