chore: fix typo in sample parallel README (#6189)

Remove redundant dot in the ksvc yaml

Author: linncy

code-samples/eventing/parallel/multiple-branches/README.md

@@ -73,7 +73,6 @@ spec:
         - name: TRANSFORMER
           value: |
             ({"message": "this is odd!"})
-.
 ```
 
 ```bash