UI: Adjust minimum size of source toolbars smaller

#5187 added a minimum size enforcement on the source toolbar to ensure
it remains functional at lower window sizes.

That minimum size was set to 800 pixels, which causes issues for
users on 1366x768 monitors in a vertical orientation.

This is still a rather common resolution, so this reduces the minimum
size below 768

UI/forms/OBSBasic.ui

@@ -205,7 +205,7 @@
       </property>
       <property name="minimumSize">
        <size>
-        <width>800</width>
+        <width>740</width>
         <height>30</height>
        </size>
       </property>

UI/forms/source-toolbar/game-capture-toolbar.ui

@@ -70,7 +70,7 @@
      </property>
      <property name="minimumSize">
       <size>
-       <width>150</width>
+       <width>120</width>
        <height>22</height>
       </size>
      </property>
@@ -117,7 +117,7 @@
      </property>
      <property name="minimumSize">
       <size>
-       <width>150</width>
+       <width>120</width>
        <height>22</height>
       </size>
      </property>