add delete character to ASCII control chars as per CommonMark v0.30

Author: hukkin

src/mdformat/codepoints/__init__.py

@@ -10,7 +10,7 @@
 from mdformat.codepoints._unicode_punctuation import UNICODE_PUNCTUATION
 from mdformat.codepoints._unicode_whitespace import UNICODE_WHITESPACE
 
-ASCII_CTRL = frozenset(chr(i) for i in range(32))
+ASCII_CTRL = frozenset(chr(i) for i in range(32)) | frozenset(chr(127))
 
 
 def __getattr__(name: str) -> frozenset[str]: