URL's with a fragment or query aren't skipped and give a file not found error

[romainmenke]

@import "foo.css#bar";
@import "foo.css?bar=baz";

These should be skipped for the same reason that url's with a protocol are skipped.

---

somewhat related to #536

[romainmenke]

Can be done with :

function isProcessableURL(uri) {
  if (/^(?:[a-z]+:)?\/\//i.test(uri)) {
    return false
  }

  try {
    // needs a base to parse properly
    const url = new URL(uri, "https://example.com")

    if (url.hash) {
      return false
    }

    if (url.search) {
      return false
    }
  } catch {} // Ignore

  return true
}