Add mediation requirement into create response parsing interface (#86)

This was omitted from #83. Adding it to the interface ensures that
clients can actually use this without having to perform additional type
checking.

src/Responses/AttestationInterface.php

@@ -9,6 +9,7 @@
     ChallengeLoaderInterface,
     CredentialInterface,
     RelyingPartyInterface,
+    Enums\CredentialMediationRequirement,
     Enums\UserVerificationRequirement,
 };
 
@@ -30,5 +31,6 @@ public function verify(
         RelyingPartyInterface $rp,
         UserVerificationRequirement $uv = UserVerificationRequirement::Preferred,
         bool $rejectUncertainTrustPaths = true,
+        CredentialMediationRequirement $mediation = CredentialMediationRequirement::Optional,
     ): CredentialInterface;
 }