(charmed-osm) Add auth to prometheus and update kafka/zk

- Authentication to prometheus:
  - Update prometheus relation to provide auth credentials (user/pass)
  - Update grafana datasource to include credentials to prometheus
- Update kafka and zookeeper charms:
  - Add support for the charms to talk to the new kafka charm
  - Add kafka and zookeeper charms in local bundle

Change-Id: Ifb83769583178f3a2069ae6756aa430ec69eecce
Signed-off-by: David Garcia <david.garcia@canonical.com>
diff --git a/installers/charm/pla/src/charm.py b/installers/charm/pla/src/charm.py
index 7867991..3238dde 100755
--- a/installers/charm/pla/src/charm.py
+++ b/installers/charm/pla/src/charm.py
@@ -90,7 +90,10 @@
     def _check_missing_dependencies(self, config: ConfigModel):
         missing_relations = []
 
-        if self.kafka_client.is_missing_data_in_unit():
+        if (
+            self.kafka_client.is_missing_data_in_unit()
+            and self.kafka_client.is_missing_data_in_app()
+        ):
             missing_relations.append("kafka")
         if not config.mongodb_uri and self.mongodb_client.is_missing_data_in_unit():
             missing_relations.append("mongodb")