UI: Clean up Update form markup

Small whitespace fix

UI/forms/OBSUpdate.ui

@@ -34,7 +34,7 @@ p, li { white-space: pre-wrap; }
 &lt;p style=&quot;-qt-paragraph-type:empty; margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; font-size:8pt;&quot;&gt;&lt;br /&gt;&lt;/p&gt;&lt;/body&gt;&lt;/html&gt;</string>
      </property>
      <property name="openExternalLinks">
-        <bool>true</bool>
+      <bool>true</bool>
      </property>
     </widget>
    </item>