Use reference strings in iaqualink (#41292)

* Update strings.json

* Update config_flow.py

* Update test_config_flow.py

homeassistant/components/iaqualink/config_flow.py

@@ -23,7 +23,7 @@ class AqualinkFlowHandler(config_entries.ConfigFlow):
         # Supporting a single account.
         entries = self.hass.config_entries.async_entries(DOMAIN)
         if entries:
-            return self.async_abort(reason="already_setup")
+            return self.async_abort(reason="single_instance_allowed")
 
         errors = {}
 
@@ -36,7 +36,7 @@ class AqualinkFlowHandler(config_entries.ConfigFlow):
                 await aqualink.login()
                 return self.async_create_entry(title=username, data=user_input)
             except AqualinkLoginException:
-                errors["base"] = "connection_failure"
+                errors["base"] = "cannot_connect"
 
         return self.async_show_form(
             step_id="user",

homeassistant/components/iaqualink/strings.json

@@ -11,10 +11,10 @@
       }
     },
     "error": {
-      "connection_failure": "Unable to connect to iAqualink. Check your username and password."
+      "cannot_connect": "[%key:common::config_flow::error::cannot_connect%]"
     },
     "abort": {
-      "already_setup": "You can only configure a single iAqualink connection."
+      "single_instance_allowed": "[%key:common::config_flow::abort::single_instance_allowed%]"
     }
   }
-}
+}

tests/components/iaqualink/test_config_flow.py

@@ -58,7 +58,7 @@ async def test_with_invalid_credentials(hass, step):
 
     assert result["type"] == "form"
     assert result["step_id"] == "user"
-    assert result["errors"] == {"base": "connection_failure"}
+    assert result["errors"] == {"base": "cannot_connect"}
 
 
 @pytest.mark.parametrize("step", ["import", "user"])