Move URL out of TheThingsNetwork strings.json (home-assistant#154760)

Author: andrew-codechimp

homeassistant/components/thethingsnetwork/config_flow.py

@@ -82,7 +82,14 @@ async def async_step_user(
             ),
             user_input,
         )
-        return self.async_show_form(step_id="user", data_schema=schema, errors=errors)
+        return self.async_show_form(
+            step_id="user",
+            data_schema=schema,
+            errors=errors,
+            description_placeholders={
+                "instructions_url": "https://www.thethingsindustries.com/docs/integrations/adding-applications/"
+            },
+        )
 
     async def async_step_reauth(
         self, entry_data: Mapping[str, Any]

homeassistant/components/thethingsnetwork/strings.json

@@ -3,7 +3,7 @@
     "step": {
       "user": {
         "title": "Connect to The Things Network v3",
-        "description": "Enter the API hostname, application ID and API key to use with Home Assistant.\n\n[Read the instructions](https://www.thethingsindustries.com/docs/integrations/adding-applications/) on how to register your application and create an API key.",
+        "description": "Enter the API hostname, application ID and API key to use with Home Assistant.\n\n[Read the instructions]({instructions_url}) on how to register your application and create an API key.",
         "data": {
           "host": "[%key:common::config_flow::data::host%]",
           "app_id": "Application ID",