Downgrade version from 13.6 to 13.5

Author: Umm-E-Kulsum

modules/compute_instance/metadata.yaml

@@ -144,7 +144,7 @@ spec:
         connections:
           - source:
               source: github.com/terraform-google-modules/terraform-google-vm//modules/instance_template
-              version: ~> 13.6
+              version: ~> 13.5
             spec:
               outputExpr: self_link
       - name: region