Adjust imports of deprecated sre_* modules in Python 3.11

Fixes HypothesisWorks#3309
See python/cpython#91308

I don't see a way to avoid relying on Python 3.11 internals here, so
this instead just adjusts the imports to avoid deprecation warnings.

hypothesis-python/src/hypothesis/strategies/_internal/regex.py

@@ -10,8 +10,13 @@
 
 import operator
 import re
-import sre_constants as sre
-import sre_parse
+
+try:  # pragma: no cover
+    import re._constants as sre
+    import re._parser as sre_parse
+except ImportError:  # Python < 3.11
+    import sre_constants as sre  # type: ignore
+    import sre_parse  # type: ignore
 
 from hypothesis import reject, strategies as st
 from hypothesis.internal.charmap import as_general_categories, categories