Add fast-path for comment detection (#9808)
## Summary
When we fall through to parsing, the comment-detection rule is a
significant portion of lint time. This PR adds an additional fast
heuristic whereby we abort if a comment contains two consecutive name
tokens (via the zero-allocation lexer). For the `ctypeslib.py`, which
has a few cases that are now caught by this, it's a 2.5x speedup for the
rule (and a 20% speedup for token-based rules).
