Add correct lifetime pattern to Notice Boards

Current Situation

• The lifetime setting for a Notice Board is broken:
  • The GUI adds the wrong variable name $epochMilli instead of $js7EpochMilli
  • As a result a wrong lifetime is calculated

Desired Behavior

• The GUI should use the $js7EpochMilli variable

Workaround

• Use the "Edit JSON" operation to modify the variable name.