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

Related-Bug: 1883468
Change-Id: I8e47bb7c70031a4df7f1af6b811df4c6cc784b2a

.zuul.yaml

@@ -628,10 +628,12 @@
             voting: false
             irrelevant-files: *dsvm-irrelevant-files
         - grenade:
+            voting: false
             irrelevant-files:
               - ^.*\.rst$
               - ^doc/.*$
         - neutron-grenade-multinode:
+            voting: false
             irrelevant-files:
               - ^.*\.rst$
               - ^doc/.*$
@@ -668,18 +670,18 @@
         - devstack-multinode
         - devstack-unit-tests
         - openstack-tox-bashate
-        - neutron-grenade-multinode:
-            irrelevant-files:
-              - ^.*\.rst$
-              - ^doc/.*$
+        # - neutron-grenade-multinode:
+        #     irrelevant-files:
+        #       - ^.*\.rst$
+        #       - ^doc/.*$
         - neutron-tempest-linuxbridge:
             irrelevant-files:
               - ^.*\.rst$
               - ^doc/.*$
-        - grenade:
-            irrelevant-files:
-              - ^.*\.rst$
-              - ^doc/.*$
+        # - grenade:
+        #     irrelevant-files:
+        #       - ^.*\.rst$
+        #       - ^doc/.*$
         - openstacksdk-functional-devstack:
             irrelevant-files:
               - ^.*\.rst$