Feature 10509 manual scaling for native k8s charm

Juju version has to be upgraded to 2.8.6 because of a typo error.
You can see bug report: https://github.com/juju/python-libjuju/issues/477
and release note: https://github.com/juju/python-libjuju/commit/facd1f19eae65728b6c7c3b823939bb35ae45ed2

Change-Id: Iae4262e64debdf6b4d36b37778ec29f0dd46bac1
Signed-off-by: aktas <emin.aktas@ulakhaberlesme.com.tr>
diff --git a/n2vc/tests/unit/utils.py b/n2vc/tests/unit/utils.py
index 2f107a7..7e8907f 100644
--- a/n2vc/tests/unit/utils.py
+++ b/n2vc/tests/unit/utils.py
@@ -159,7 +159,7 @@
     async def is_leader_from_status(self):
         return True
 
-    async def run_action(self, action_name):
+    async def run_action(self, action_name, **kwargs):
         return FakeAction()
 
 
@@ -176,6 +176,9 @@
     async def get_config(self):
         return ["app_config"]
 
+    async def scale(self, scale):
+        pass
+
     units = [FakeUnit(), FakeUnit()]