Improve testing of FactCache (#55739)

* Improve testing of FactCache

test/units/plugins/cache/test_cache.py

@@ -117,6 +117,14 @@ class TestFactCache(unittest.TestCase):
                                     "Unable to load the facts cache plugin.*json.*",
                                     FactCache)
 
+    def test_update(self):
+        self.cache.update({'cache_key': {'key2': 'updatedvalue'}})
+        assert self.cache['cache_key']['key2'] == 'updatedvalue'
+
+    def test_update_legacy(self):
+        self.cache.update('cache_key', {'key2': 'updatedvalue'})
+        assert self.cache['cache_key']['key2'] == 'updatedvalue'
+
     def test_update_legacy_key_exists(self):
         self.cache['cache_key'] = {'key': 'value', 'key2': 'value2'}
         self.cache.update('cache_key', {'key': 'updatedvalue'})