Tiny tweak to Geyser cooldown for better Redstone control

Currently, any change to the Magma Block / Potent Sulfur / Water setup resets the geyser's cooldown to its maximum. Technically you can control this with Pistons/Dispensers, but the 20-60 second delay between input and result makes it difficult to meaningfully use.

With the tiny change that the cooldown keeps counting down even if the water above is removed, this would allow for much finer control - the geyser still needs to spend some time building up heat/pressure like a real-world one, but the eruption can be delayed until needed.
(Ideally with some smoke particles to show when the block would be ready to fire, but can't yet due to the missing water.)