fix: Add re.Pattern to allowed match types (#497)

Suggested in #436 (comment)

Author: robertschweizer

releasenotes/notes/add-re-pattern-to-match-types-6a4c1d9e64e2a5e1.yaml

@@ -0,0 +1,4 @@
+---
+fixes:
+  - |
+    Added `re.Pattern` to allowed match types.

tenacity/retry.py

@@ -207,7 +207,7 @@ class retry_if_exception_message(retry_if_exception):
     def __init__(
         self,
         message: typing.Optional[str] = None,
-        match: typing.Optional[str] = None,
+        match: typing.Union[None, str, typing.Pattern[str]] = None,
     ) -> None:
         if message and match:
             raise TypeError(
@@ -242,7 +242,7 @@ class retry_if_not_exception_message(retry_if_exception_message):
     def __init__(
         self,
         message: typing.Optional[str] = None,
-        match: typing.Optional[str] = None,
+        match: typing.Union[None, str, typing.Pattern[str]] = None,
     ) -> None:
         super().__init__(message, match)
         # invert predicate