QMake: Remove stray margins on BuildConfiguration widget

Change-Id: Iaed2a52dac6cb025d5e54309f1c569139c10568b
Reviewed-by: Cristian Adam <cristian.adam@gmail.com>
Reviewed-by: Niels Weber <niels.weber@theqtcompany.com>

src/plugins/qmakeprojectmanager/qmakeprojectconfigwidget.ui

@@ -7,10 +7,22 @@
     <x>0</x>
     <y>0</y>
     <width>408</width>
-    <height>78</height>
+    <height>62</height>
    </rect>
   </property>
   <layout class="QGridLayout" name="gridLayout">
+   <property name="leftMargin">
+    <number>0</number>
+   </property>
+   <property name="topMargin">
+    <number>0</number>
+   </property>
+   <property name="rightMargin">
+    <number>0</number>
+   </property>
+   <property name="bottomMargin">
+    <number>0</number>
+   </property>
    <item row="0" column="0">
     <widget class="QLabel" name="shadowBuildLabel">
      <property name="text">