Fix typing issues detected by pylance

Change-Id: Id5dbc01e34e83abccb7dbbaba8edc6f7ec658ddd
Signed-off-by: garciadeblas <gerardo.garciadeblas@telefonica.com>
diff --git a/osm_lcm/n2vc/k8s_conn.py b/osm_lcm/n2vc/k8s_conn.py
index 33e868a..092a6fa 100644
--- a/osm_lcm/n2vc/k8s_conn.py
+++ b/osm_lcm/n2vc/k8s_conn.py
@@ -61,7 +61,7 @@
     @abc.abstractmethod
     async def init_env(
         self, k8s_creds: str, namespace: str = "kube-system", reuse_cluster_uuid=None
-    ) -> (str, bool):
+    ) -> tuple[str, bool]:
         """
         It prepares a given K8s cluster environment to run Charts or juju Bundles on
         both sides: