Attempt to fix ReDoS issue.

Author: htorianik-amplify

hcl2/transformer.py

@@ -6,8 +6,8 @@
 
 from lark.visitors import Transformer, Discard, _DiscardType
 
-HEREDOC_PATTERN = re.compile(r"<<([a-zA-Z][a-zA-Z0-9._-]+)\n((.|\n)*)\1", re.S)
-HEREDOC_TRIM_PATTERN = re.compile(r"<<-([a-zA-Z][a-zA-Z0-9._-]+)\n((.|\n)*)\1", re.S)
+HEREDOC_PATTERN = re.compile(r"<<([a-zA-Z][a-zA-Z0-9._-]+)\n([\s\S]*)\1", re.S)
+HEREDOC_TRIM_PATTERN = re.compile(r"<<-([a-zA-Z][a-zA-Z0-9._-]+)\n([\s\S]*)\1", re.S)
 
 Attribute = namedtuple("Attribute", ("key", "value"))