Moved the password icon to the room name.

Also added a dark mode lock icon as well (and fixed a small bug
preventing the lock icon from showing up)

dist/qt_themes/qdarkstyle/style.qrc

@@ -1,6 +1,7 @@
 <RCC>
   <qresource prefix="icons/qdarkstyle">
     <file alias="index.theme">icons/index.theme</file>
+    <file alias="16x16/lock.png">icons/16x16/lock.png</file>
   </qresource>
   <qresource prefix="qss_icons">
     <file>rc/up_arrow_disabled.png</file>