We landed a change that added a new `InterpreterDirective` AST node type for hashbangs, and no longer add it as a comment/leadingComment.
Ref: https://github.com/babel/babel/pull/7928
I mimicked what we do in `@babel/generator` here, since I found it better than trying to add comments to the ast in `parser-include-shebang.js`). Definitely open to a better/cleaner option though!
Note: I'll follow this up with enabling tests for https://github.com/prettier/prettier/pull/4543 and https://github.com/prettier/prettier/pull/4540 once they land too.