Crashes caused by the missing AWT dependency come up in the support channels fairly often.
This patch detects the missing dependency and stops the server with a clear error message,
containing a link to instructions on how to install a non-headless JRE.
Fixes https://github.com/PaperMC/Paper/issues/7276 and https://github.com/PaperMC/Paper/issues/8118
by using a config option that, when set to false, does not add markers to the entity
tick list at all and ignores them in Spigot's activation range checks. The entity tick
list is only used in the tick and tickPassenger methods, so we can safely not add the
markers to it. When the config option is set to true, markers are ticked as normal.
Noah van der Aa