Work around uwsgi breakage

uwsgi broke installation from source with their latest release [0].
Since we want to move away from source installation anyway, make
grenade based jobs non-voting for the moment so that we can backport
[1] properly.

[0] https://bugs.launchpad.net/bugs/1883468
[1] https://review.opendev.org/577955

Change-Id: I3891e4eda3c459acefa0d3c028cda649b984ff0c
Related-Bug: 1883468

zuul.d/project-templates.yaml

@@ -1867,12 +1867,13 @@
       repositories in the integrated gate.
     check:
       jobs:
-        - grenade
+        - grenade:
+            voting: false
         - tempest-full-py3:
             branches: ^(?!(stable/(newton|ocata|pike)|driverfixes)).*$
     gate:
       jobs:
-        - grenade
+        #- grenade
         - tempest-full-py3:
             branches: ^(?!(stable/(newton|ocata|pike)|driverfixes)).*$