fdo#81036 escape ~ in .ui and fix a typo (straight apostrophe)

Change-Id: I652dc63cc0e8fb04d7c3115d66d60dabda60f0f4

starmath/uiconfig/smath/ui/smathsettings.ui

@@ -239,7 +239,7 @@
                 <property name="spacing">6</property>
                 <child>
                   <object class="GtkCheckButton" id="norightspaces">
-                    <property name="label" translatable="yes">Ig_nore ~ and ` at the end of the line</property>
+                    <property name="label" translatable="yes">Ig_nore ~~ and ' at the end of the line</property>
                     <property name="visible">True</property>
                     <property name="can_focus">True</property>
                     <property name="receives_default">False</property>