frontend: Add close icon

frontend/forms/images/close.svg

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<svg height="16px" viewBox="0 0 16 16" width="16px" xmlns="http://www.w3.org/2000/svg">
+    <path d="m 4 4 h 1 h 0.03125 c 0.253906 0.011719 0.511719 0.128906 0.6875 0.3125 l 2.28125 2.28125 l 2.3125 -2.28125 c 0.265625 -0.230469 0.445312 -0.304688 0.6875 -0.3125 h 1 v 1 c 0 0.285156 -0.035156 0.550781 -0.25 0.75 l -2.28125 2.28125 l 2.25 2.25 c 0.1875 0.1875 0.28125 0.453125 0.28125 0.71875 v 1 h -1 c -0.265625 0 -0.53125 -0.09375 -0.71875 -0.28125 l -2.28125 -2.28125 l -2.28125 2.28125 c -0.1875 0.1875 -0.453125 0.28125 -0.71875 0.28125 h -1 v -1 c 0 -0.265625 0.09375 -0.53125 0.28125 -0.71875 l 2.28125 -2.25 l -2.28125 -2.28125 c -0.210938 -0.195312 -0.304688 -0.46875 -0.28125 -0.75 z m 0 0" fill="#202020"/>
+</svg>

frontend/forms/obs.qrc

@@ -1,5 +1,6 @@
 <RCC>
   <qresource prefix="/res">
+    <file>images/close.svg</file>
     <file>images/save.svg</file>
     <file>images/media-pause.svg</file>
     <file>images/trash.svg</file>