fix: incorrect check of proof.created

Signed-off-by: Timo Glastra <[email protected]>

Author: TimoGlastra

aries_cloudagent/protocols/issue_credential/v2_0/formats/ld_proof/handler.py

@@ -445,7 +445,7 @@ async def receive_credential(
         # TODO: if created wasn't present in the detail options, should we verify
         # it is ~now (e.g. some time in the past + future)?
         # Check if created property matches
-        if vc.proof.created != detail.options.created:
+        if detail.options.created and vc.proof.created != detail.options.created:
             raise V20CredFormatError(
                 "Received credential proof.created does not"
                 " match options.created from credential request"