test lazy character class (#180)

There is an issue with the compiler and lazy character classes.

The test I have added will raise the following exception:
`RuntimeError: [12:25:32] /workspace/cpp/grammar_parser.cc:78: EBNF
parse error at line 1, column 16: Expect element`

tests/python/test_grammar_matcher_regex.py

@@ -84,6 +84,8 @@ def test_regex_refuse(regex_input_refused: str):
     (r"[a-z0-9]+", "ABC", False),
     (r"[^abc]+", "def", True),
     (r"[^abc]+", "aaa", False),
+    # Lazy character class
+    (r"[abc]+?abc", "aabc", True),
     # Quantifiers
     (r"a*b+c?", "b", True),
     (r"a*b+c?", "aaabbc", True),