Check if challenge is already approved before raising exception (#5445)

Author: whitdog47

src/dispatch/plugins/dispatch_core/plugin.py

@@ -379,6 +379,9 @@ def validate_mfa_token(
             raise ActionMismatchError("Action mismatch")
         if not challenge.valid:
             raise ExpiredChallengeError("Challenge is no longer valid")
+        if challenge.status == MfaChallengeStatus.APPROVED:
+            # Challenge has already been approved
+            return challenge.status
         if challenge.status != MfaChallengeStatus.PENDING:
             raise InvalidChallengeStateError(f"Challenge is in invalid state: {challenge.status}")