Fix typo: redex -> regex

Author: delirious-lettuce

prompt_toolkit/contrib/regular_languages/compiler.py

@@ -70,7 +70,7 @@ def __init__(self, root_node, escape_funcs=None, unescape_funcs=None):
  self.escape_funcs = escape_funcs or {}
  self.unescape_funcs = unescape_funcs or {}
 
- #: Dictionary that will map the redex names to Node instances.
+ #: Dictionary that will map the regex names to Node instances.
  self._group_names_to_nodes = {} # Maps regex group names to varnames.
  counter = [0]