Add type hint Database for all activity classes requiring it

Change-Id: Ib1de26817a5ecff7f14080e45aa9b22829bd747c
Signed-off-by: Dario Faccin <dario.faccin@canonical.com>
diff --git a/osm_lcm/temporal/vim_activities.py b/osm_lcm/temporal/vim_activities.py
index 4259fa8..4bd5514 100644
--- a/osm_lcm/temporal/vim_activities.py
+++ b/osm_lcm/temporal/vim_activities.py
@@ -27,17 +27,18 @@
     UpdateVimOperationStateInput,
     UpdateVimStateInput,
 )
+from osm_lcm.data_utils.database.database import Database
 
 
 class VimDbActivity:
     """Perform Database operations for VIM accounts.
 
     Args:
-        db  (object):       Data Access Object
+        db  (Database):       Data Access Object
     """
 
-    def __init__(self, db):
-        self.db = db
+    def __init__(self, db: Database):
+        self.db: Database = db
         self.logger = logging.getLogger(f"lcm.act.{self.__class__.__name__}")
 
     @activity.defn(name=ACTIVITY_UPDATE_VIM_STATE)