Updating unit tests for NBI charm

Change-Id: I21f92498364691c225164faa580788e07e133f47
Signed-off-by: sousaedu <eduardo.sousa@canonical.com>
diff --git a/installers/charm/nbi/src/pod_spec.py b/installers/charm/nbi/src/pod_spec.py
index 105e877..68915de 100644
--- a/installers/charm/nbi/src/pod_spec.py
+++ b/installers/charm/nbi/src/pod_spec.py
@@ -28,7 +28,6 @@
     IPvAnyNetwork,
     PositiveInt,
     validator,
-    ValidationError,
 )
 from typing import Any, Dict, List, Optional
 from urllib.parse import urlparse
@@ -78,7 +77,7 @@
 
     message_host: str
     message_port: PositiveInt
-    database_uri: constr(regex=r"^(mongo://)")
+    database_uri: constr(regex=r"^(mongodb://)")
     prometheus_host: str
     prometheus_port: PositiveInt
     keystone: bool