Changes openstack vim status check to use nova to allow non admin users in config

Change-Id: I1cdfeac879580a61e0211e869785c737763cd310
Signed-off-by: Benjamin Diaz <bdiaz@whitestack.com>
diff --git a/osm_mon/collector/infra_collectors/base_osinfra.py b/osm_mon/collector/infra_collectors/base_osinfra.py
index 278cc20..afbf245 100644
--- a/osm_mon/collector/infra_collectors/base_osinfra.py
+++ b/osm_mon/collector/infra_collectors/base_osinfra.py
@@ -76,7 +76,7 @@
 
     def is_vim_ok(self) -> bool:
         try:
-            self.keystone.projects.list()
+            self.nova.servers.list()
             return True
         except Exception:
             log.exception("VIM status is not OK!")