Improve AppStream metainfo

- Correct the software license to be GPL-2.0-or-later.
- Remove the hyphen in the developer name.
- Add social-audio intense due to unmoderated voice chat.
- Some syntax / order changes to match ioquake3's metainfo.

engine/misc/setup/com.q3rally.Q3Rally.metainfo.xml

@@ -1,12 +1,11 @@
-<?xml version='1.0' encoding='utf-8'?>
-<component type="desktop">
-  <!--Created with jdAppStreamEdit 7.0-->
+<?xml version="1.0" encoding="UTF-8"?>
+<component type="desktop-application">
   <id>com.q3rally.Q3Rally</id>
+  <launchable type="desktop-id">q3rally.desktop</launchable>
+  <metadata_license>CC0-1.0</metadata_license>
+  <project_license>GPL-2.0-or-later</project_license>
   <name>Q3Rally</name>
   <summary>Survival racing game</summary>
-  <developer_name>Q3Rally-Team</developer_name>
-  <metadata_license>CC0-1.0</metadata_license>
-  <project_license>GPL-2.0-only</project_license>
   <description>
     <p>Q3Rally is a vehicular combat racing game.</p>
   </description>
@@ -50,8 +49,10 @@
   <url type="homepage">http://www.q3rally.com/</url>
   <url type="bugtracker">https://github.com/Q3Rally-Team/q3rally/issues</url>
   <url type="vcs-browser">https://github.com/Q3Rally-Team/q3rally</url>
+  <developer_name>Q3Rally Team</developer_name>
   <content_rating type="oars-1.1">
     <content_attribute id="violence-fantasy">moderate</content_attribute>
     <content_attribute id="social-chat">intense</content_attribute>
+    <content_attribute id="social-audio">intense</content_attribute>
   </content_rating>
 </component>