Move openSUSE to experimental status

Zuul jobs for openSUSE are moved to non-voting for the remainder of the
Ussuri cycle and will be removed early in the Victoria cycle.

Change-Id: I3ffd285236e8d9575ffd1817bdf2cfc77d6ad5d4

doc/source/user/aio/quickstart.rst

@@ -129,7 +129,8 @@ version.
 .. note::
    The |current_release_formal_name| release is only compatible with
    Debian 9 (stretch), Debian 10 (buster), Ubuntu 18.04 (Bionic Beaver),
-   CentOS 7 and openSUSE Leap 15.X.
+   CentOS 7. Experimentat support is provided for openSUSE Leap 15.X
+   but this is expected to be removed in the next major release.
 
 The next step is to bootstrap Ansible and the Ansible roles for the
 development environment.

releasenotes/notes/suse_experimental-247d141fe0381f21.yaml

@@ -0,0 +1,7 @@
+---
+deprecations:
+  - |
+    Support for openSUSE in Ussuri is moved from fully supported to
+    experimental due to insufficient resources to maintain reliable
+    CI jobs. The zuul jobs are moved to be non-voting. Support will
+    be removed entirely in the Victoria cycle.

zuul.d/project-templates.yaml

@@ -68,7 +68,6 @@
       jobs:
         - openstack-ansible-deploy-aio_metal-debian-buster
         - openstack-ansible-deploy-aio_metal-centos-7
-        - openstack-ansible-deploy-aio_metal-opensuse-15
         - openstack-ansible-deploy-aio_metal-ubuntu-bionic
         - openstack-ansible-upgrade-aio_metal-centos-7:
             voting: false
@@ -77,9 +76,8 @@
       jobs:
         - openstack-ansible-deploy-aio_metal-debian-buster
         - openstack-ansible-deploy-aio_metal-centos-7
-        - openstack-ansible-deploy-aio_metal-opensuse-15
         - openstack-ansible-deploy-aio_metal-ubuntu-bionic
-    periodic:
+    experimental:
       jobs:
         - openstack-ansible-deploy-aio_metal-opensuse-15
 
@@ -104,14 +102,12 @@
     check:
       jobs:
         - openstack-ansible-deploy-aio_distro_metal-centos-7
-        - openstack-ansible-deploy-aio_distro_metal-opensuse-15:
-            voting: false
         - openstack-ansible-deploy-aio_distro_metal-ubuntu-bionic
     gate:
       jobs:
         - openstack-ansible-deploy-aio_distro_metal-centos-7
         - openstack-ansible-deploy-aio_distro_metal-ubuntu-bionic
-    periodic:
+    experimental:
       jobs:
         - openstack-ansible-deploy-aio_distro_metal-opensuse-15