Replace doc_comments_and_attrs with collect_attrs

[HKalbasi]

fix #16063

I looked at the other usages of doc_comments_and_attrs and it seems all of them are prone to ignoring inner attributes. @Veykril should I replace all of those with collect_attrs and remove doc_comments_and_attrs (or even HasDocComments) entirely?

[HKalbasi]

I'm going to merge this for now. Will replace remaining usages of doc_comments_and_attrs in another PR if desired.

@bors r+

[bors]

📌 Commit 9337519 has been approved by HKalbasi

It is now in the queue for this repository.

[bors]

⌛ Testing commit 9337519 with merge 9d87a23...

[Veykril]

We should replace the other ones as well, though the one in semantics needs special casing depending on whether we are working with inner attributes or not.

Also the issue here is actually just

   mod _test_inner {
        #![empty_attr]
      //^^^^^^^^^^^^^^ error: unresolved macro `empty_attr`
    }

the extern crate is irrelevant

[bors]

☀️ Test successful - checks-actions
Approved by: HKalbasi
Pushing 9d87a23 to master...