swaylock: Fix caps lock not updating immediately

[oscarwcl]

Partially fixes #2788. This change makes it so the lock screen is redrawn whenever the caps lock modifier state changes, rather on relying on the keypress event. This didn't work because caps lock is disabled when the key is released, not pressed, so the caps lock indicator does not go away until the next keypress event.

This doesn't fully implement the suggestions in #2788, but is a more basic fix that just makes it so the caps lock indicator is always accurate. I'd be happy to have a go implementng them if anyone's interested, although it doesn't personally seem to me that they'd be that useful.

[RedSoxFan]

This doesn't fully implement the suggestions in #2788, but is a more basic fix that just makes it so the caps lock indicator is always accurate. I'd be happy to have a go implementng them if anyone's interested, although it doesn't personally seem to me that they'd be that useful.

It looks like there are three things in that issue:

1. Persistent Caps Lock ON with Caps Lock OFF for the next key press
   This PR mostly hits this bullet, it's just missing the Caps Lock OFF for a key press. Personally, I think this is good enough and if someone really wants the last bit, another PR (or even a local patch) can be submitted/applied.

2. --indicator-ring-caps-lock (along with something like --disable-caps-lock-text)
   I do like this idea, but it can be done in a separate PR.

3. Only showing caps lock on entry
   If this does get implements, I think it should be optional, but I don't personally have any strong opinion either way on implementing this.

[ddevault]

Thanks!

[colemickens]

Cool, another thank you from me!