fix: use correct matching rule serialisation

The serialisation used internally for `with_matching_rules` used the
default JSON encoder. This now has been fixed and allows for matchers to
be used directly.

Signed-off-by: JP-Ellis <josh@jpellis.me>

Author: JP-Ellis

src/pact/interaction/_base.py

@@ -16,7 +16,7 @@
 from typing import TYPE_CHECKING, Any, Literal
 
 import pact_ffi
-from pact.match.matcher import IntegrationJSONEncoder
+from pact.match.matcher import IntegrationJSONEncoder, MatchingRuleJSONEncoder
 
 if TYPE_CHECKING:
     from pathlib import Path
@@ -556,7 +556,7 @@ def with_matching_rules(
                 response.
         """
         if isinstance(rules, dict):
-            rules = json.dumps(rules)
+            rules = json.dumps(rules, cls=MatchingRuleJSONEncoder)
 
         pact_ffi.with_matching_rules(
             self._handle,

src/pact/match/matcher.py

@@ -424,8 +424,12 @@ def default(self, o: Any) -> Any:  # noqa: ANN401
         Returns:
             The encoded object.
         """
-        if isinstance(o, AbstractMatcher):
+        if isinstance(o, AndMatcher):
             return o.to_matching_rule()
+        if isinstance(o, AbstractMatcher):
+            # We need to convert all matchers in AndMatchers (even if there is
+            # only one).
+            return AndMatcher(o).to_matching_rule()
         return super().default(o)