message: Update mainwindow.ui change Unspendable to Unconfirmed
diff: @@ -182,7 +182,7 @@ font-size: 24px;
  color: #707070;</string>
  </property>
  <property name="text">
  - <string>Unspendable</string>
  + <string>Unconfirmed</string>
  </property>
  <property name="alignment">
  <set>Qt::AlignCenter</set>
  