Update swagger.json (#5439) [skip ci]

Fix: /API Key/apikey generation when using the https://radarr.video/docs/api/ and setting an api key.

It currently generates this output which will not work with Radarr v3

```
curl -X GET "http://localhost:7878/api/v3/system/status?API%20Key=awawfaw" -H "accept: application/json"
```

src/Radarr.Api.V3/swagger.json

@@ -3994,7 +3994,7 @@
         "description": "Used when not providing the key via URL"
       },
       "apikey": {
-        "name": "API Key",
+        "name": "apikey",
         "type": "apiKey",
         "in": "query",
         "description": "Used when not providing the key via header"
@@ -4045,4 +4045,4 @@
       "name": "System"
     }
   ]
-}
+}