Drop GlusterFS jobs

These jobs were removed from manila[1], because the drivers were
deprecated.

The job definitions are still kept to be used in stable branches.

[1] a50f699d449ac286c9ea4a9617abf8fc60845f2e

Change-Id: I5a1126f1c0a9c0f0d83569b5c4de37e1ecdbfca4
diff --git a/zuul.d/project.yaml b/zuul.d/project.yaml
index 46d8e5b..68366a3 100644
--- a/zuul.d/project.yaml
+++ b/zuul.d/project.yaml
@@ -15,13 +15,7 @@
         - manila-tempest-plugin-dummy-no-dhss-rbac
         - manila-tempest-plugin-container:
             voting: false
-        - manila-tempest-plugin-glusterfs-nfs:
-            voting: false
     gate:
       jobs:
         - manila-tempest-plugin-dummy-no-dhss
         - manila-tempest-plugin-dummy-dhss
-    experimental:
-      jobs:
-        - manila-tempest-plugin-glusterfs-native:
-            voting: false