Consider using swaylock-effects

[FilippoBonazziSUSE]

From #146:

Potentially as more of an eye-candy we could also consider using swaylock-effects instead of swaylock which does a blurring of the background for the lockscreen bg, and supports clock & date, fade in/out etc.
(https://github.com/jirutka/swaylock-effects)

Previous discussion in #39

[FilippoBonazziSUSE]

This gets a no from me, since this adds complexity to the configuration, a potentially unstable upstream to deal with, and should rather be added to a user configuration.