Improve consistency of sensor strings to reduce confusion in NUT (#12…

…4184)

Improve consistency of sensor strings to reduce confusion

homeassistant/components/nut/strings.json

@@ -127,8 +127,8 @@
       "input_l1_current": { "name": "Input L1 current" },
       "input_l2_current": { "name": "Input L2 current" },
       "input_l3_current": { "name": "Input L3 current" },
-      "input_frequency": { "name": "Input line frequency" },
-      "input_frequency_nominal": { "name": "Nominal input line frequency" },
+      "input_frequency": { "name": "Input frequency" },
+      "input_frequency_nominal": { "name": "Input nominal frequency" },
       "input_frequency_status": { "name": "Input frequency status" },
       "input_l1_frequency": { "name": "Input L1 line frequency" },
       "input_l2_frequency": { "name": "Input L2 line frequency" },