Replace exception (that was never being caught) with a log message to…

… indicate a missing receipt.

Signed-off-by: pfeairheller <[email protected]>

src/keri/app/agenting.py

@@ -96,7 +96,7 @@ def receipt(self, pre, sn=None):
                 coring.Counter(qb64b=rct, strip=True)
                 rcts[wit] = rct
             else:
-                raise kering.ValidationError(f"invalid response {rep.status} from witnesses {wit}")
+                logger.error(f"invalid response {rep.status} from witnesses {wit}")
 
         for wit in rcts.keys():
             ewits = [w for w in rcts.keys() if w != wit]