Upstream has released updates that appear to apply and compile correctly.
This update has not been tested by PaperMC and as with ANY update, please do your own testing
Bukkit Changes:
312281ea PR-742: Make World implement Keyed
CraftBukkit Changes:
2ac7fa7a SPIGOT-7014: getLootTable API should not persistently update loot table
7fdd7941 PR-1046: Make World implement Keyed
7bc728a6 PR-1045: Revert changes to persistence required checks
Spigot Changes:
b6d12d17 Rebuild patches
Also adds per-world spawn limit config in paper.yml for `underground_water_creature`, and migrates existing spawn limit config options to their Mojang names.