fix: Removed left-over, redundant lxml import from bnf_grammar_processor

Author: hpdekoning

tool-support/bnf_grammar_tools/bnf_grammar/bnf_grammar_processor.py

@@ -38,8 +38,6 @@
 # Create logger for diagnostic messages at debug, info, warning, error and critical levels
 import logging
 
-from lxml.html.defs import list_tags
-
 LOGGER: Logger = logging.getLogger()
 
 # Marker denoting start of a line comment in generated output