Update matcher pattern validation tests (#12835)

- parametrize over individual token patterns (as originally intended, as
far as I can tell)
- add a test for lowercase `in` in patterns

spacy/tests/matcher/test_pattern_validation.py

@@ -52,7 +52,8 @@ TEST_PATTERNS = [
 
 
 @pytest.mark.parametrize(
-    "pattern", [[{"XX": "y"}, {"LENGTH": "2"}, {"TEXT": {"IN": 5}}]]
+    "pattern",
+    [[{"XX": "y"}], [{"LENGTH": "2"}], [{"TEXT": {"IN": 5}}], [{"text": {"in": 6}}]],
 )
 def test_matcher_pattern_validation(en_vocab, pattern):
     matcher = Matcher(en_vocab, validate=True)