Add Steam Group Announcements Bridge (#3527)

* Create SteamGroupAnnouncementsBridge.php

* Shorten implementation

Maybe this fixes the tests

* test

---------

Co-authored-by: Dag <me@dvikan.no>

bridges/SteamGroupAnnouncementsBridge.php

@@ -0,0 +1,25 @@
+<?php
+
+class SteamGroupAnnouncementsBridge extends FeedExpander
+{
+    const MAINTAINER = 'Jisagi';
+    const NAME = 'Steam Group Announcements';
+    const URI = 'https://steamcommunity.com/';
+    const DESCRIPTION = 'Returns latest announcements from a steam group.';
+
+    const PARAMETERS = [
+        [
+            'g' => [
+                'name' => 'Group name',
+                'exampleValue' => 'freegamesfinders',
+                'required' => true
+            ]
+        ]
+    ];
+
+    public function collectData()
+    {
+        $uri = self::URI . 'groups/' . $this->getInput('g') . '/rss';
+        $this->collectExpandableDatas($uri, 10);
+    }
+}