Added tests for update command

unittests/unittests_shared/cli_commands.py

@@ -78,6 +78,10 @@ class CLICommands:
     def uninstall(cls, package: str, output=False):
         cls._run('uninstall', package, output=output)
 
+    @classmethod
+    def update(cls, output=False):
+        cls._run('update', output=output)
+
     @classmethod
     def version(cls) -> str:
         return cls._run_with_output('version')