Waxed sign still triggers Observer (waxed sign = button with instant pulse)

Key idea: Interacting with a waxed sign should still trigger an Observer watching the sign, allowing signs to be used like buttons.

In Bedrock, it's already the case that: For a sign watched by an Observer, when you exit the text editing screen, the Observer will be triggered (even if you didn't actually change any text).

However, a waxed sign can't be edited, even though you can interact with the sign (it makes a squishy honey noise when you do).  Just change it so this interaction will trigger the Observer, just as if you had edited the sign. 

This would allow signs to be used like buttons, enabling us to make interfaces more compact, as well as providing a new kind of button that sends out a single instantaneous pulse, rather than staying pressed for 1/1.5 seconds like stone/wooden buttons.  Currently, for the end-user of a contraption to trigger such a pulse, they need to do something awkward like flip a trapdoor or hit a note block (or flip a lever, which can be misleading).  Interacting with a sign would be a more natural way to send a pulse.

This should not break any contraptions since, if a player doesn't want a sign to trigger Redstone, then they just won't have an Observer watching it in the first place.

This would also be a fairly easy change as the game clearly already understands the player is interacting with the waxed sign, and the logic is already there to trigger an Observer upon a interaction.

Simple but useful tweak.