translation string fix

Author: jef-n

src/ui/qgsattributetypeedit.ui

@@ -20,7 +20,7 @@
    <item row="4" column="1">
     <widget class="QgsCollapsibleGroupBox" name="groupBox">
      <property name="title">
-      <string>Contraints</string>
+      <string>Constraints</string>
      </property>
      <layout class="QVBoxLayout" name="verticalLayout">
       <item>