Use $() to return matched string instead of head:* tail:*

[dmsnell]

No description provided.

[aduth]

I have no context for the motivation or impact of this change.

[ntwb]

This shouldn't be in the same pull request as a proposed code change, a separate pull request "if any".

This really should be added to your global .gitignore, there are too many IDEs and Editors to accomadate, see https://core.trac.wordpress.org/changeset/35254

[dmsnell]

I have no context for the motivation or impact of this change.

@aduth just a little cleanup to a simpler way - shouldn't cause any functional changes

[nylen]

From https://pegjs.org/documentation#grammar-syntax-and-semantics:

$ expression
Try to match the expression. If the match succeeds, return the matched text instead of the match result.

Remove the .idea change and