Remove Jackett api key from widget

The Jackett widget was using the api key in api requests however this
is not necessary as the endpoint we use doesn't require it. If Jackett
authentication is enabled then the password field should be used
instead.

docs/widgets/services/jackett.md

@@ -13,6 +13,5 @@ Allowed fields: `["configured", "errored"]`.
 widget:
   type: jackett
   url: http://jackett.host.or.ip
-  key: jackettapikey
   password: JackettAdminPassword
 ```

src/widgets/jackett/widget.js

@@ -1,7 +1,7 @@
 import credentialedProxyHandler from "utils/proxy/handlers/credentialed";
 
 const widget = {
-  api: "{url}/api/v2.0/{endpoint}?apikey={key}&configured=true",
+  api: "{url}/api/v2.0/{endpoint}?configured=true",
   proxyHandler: credentialedProxyHandler,
   loginURL: "{url}/UI/Dashboard",