[Queens-Only] Remove Glance's nfs hardcoded version

Glance nfs version is hardcoded in tripleo which makes the fstab
entry with nfs version 4 even though user sets another version
via 'GlanceNfsOptions' parameter.

Since this issues has been fixed in rocky during one nfs cleanup
patch[1], we just need to fix this in Queens.

Note: Partial-cherrypick of [1] is not possible here because glance
nfs part of code is moved to another file.

[1]: https://review.openstack.org/#/c/576043/

Change-Id: I0256ceae17bc7be2c9dfa7a8e12bb70c89eba14c
Closes-Bug: #1815011

docker/services/glance-api.yaml

@@ -241,7 +241,7 @@ outputs:
         - - name: Mount NFS on host
             vars:
               nfs_backend_enable: {get_param: GlanceNfsEnabled}
-            mount: name=/var/lib/glance/images src="{{item.NFS_SHARE}}" fstype=nfs4 opts="{{item.NFS_OPTIONS}}" state=mounted
+            mount: name=/var/lib/glance/images src="{{item.NFS_SHARE}}" fstype=nfs opts="{{item.NFS_OPTIONS}}" state=mounted
             with_items:
               - NFS_SHARE: {get_param: GlanceNfsShare}
                 NFS_OPTIONS: {get_param: GlanceNfsOptions}