Enhance maximum for point displacement tolerance (ticket #4319)

Author: mhugent

src/plugins/point_displacement_renderer/qgspointdisplacementrendererwidgetbase.ui

@@ -130,7 +130,7 @@
            <number>7</number>
           </property>
           <property name="maximum">
-           <double>9999.000000000000000</double>
+           <double>999999999.000000000000000</double>
           </property>
          </widget>
         </item>