Updated Upstream (BungeeCord)

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

BungeeCord Changes:
8f6768ae Bump version to 1.21-R0.5-SNAPSHOT
70603d54 Release 1.21-R0.4
2e12caad Add central-publishing-maven-plugin
f9ce9fad #3884: Add docs for Plugin#getExecutorService
69b476fc #3881: Optimize ServerUnique Tablist code
d37a430f #3882: Reduce lock boilerplate by using lomboks `@Locked`
4c02676b #3883: Minecraft 1.21.9-rc1 support

Author: electronicboy