fix: concurrency issue in ServerEntity#sendDirtyEntityData()

[bridgelol]

No description provided.

[DarkyG2]

it was to fix this error:

[20:38:09] [Region Scheduler Thread #2/ERROR]: [io.papermc.paper.threadedregions.TickRegionScheduler] Region #2182 centered at chunk [-1002, -525] in world 'claim_world' failed to tick:
net.minecraft.ReportedException: Exception ticking world
  at net.minecraft.server.MinecraftServer.tickChildren(MinecraftServer.java:1858) ~[luminol-1.20.4.jar:git-Luminol-"5579f65"]
  at net.minecraft.server.dedicated.DedicatedServer.tickChildren(DedicatedServer.java:449) ~[luminol-1.20.4.jar:git-Luminol-"5579f65"]
  at net.minecraft.server.MinecraftServer.tickServer(MinecraftServer.java:1671) ~[luminol-1.20.4.jar:git-Luminol-"5579f65"]
  at io.papermc.paper.threadedregions.TickRegions$ConcreteRegionTickHandle.tickRegion(TickRegions.java:408) ~[luminol-1.20.4.jar:git-Luminol-"5579f65"]
  at io.papermc.paper.threadedregions.TickRegionScheduler$RegionScheduleHandle.runTick(TickRegionScheduler.java:404) ~[luminol-1.20.4.jar:git-Luminol-"5579f65"]
  at ca.spottedleaf.concurrentutil.scheduler.SchedulerThreadPool$TickThreadRunner.run(SchedulerThreadPool.java:525) ~[luminol-1.20.4.jar:git-Luminol-"5579f65"]
  at java.lang.Thread.run(Thread.java:1583) ~[?:?]
Caused by: java.lang.NullPointerException: Cannot invoke "it.unimi.dsi.fastutil.objects.ReferenceArrayList.get(int)" because "this.wrapped" is null
  at it.unimi.dsi.fastutil.objects.ReferenceOpenHashSet$SetIterator.next(ReferenceOpenHashSet.java:520) ~[fastutil-8.5.12.jar:?]
  at org.bukkit.craftbukkit.v1_20_R3.entity.CraftPlayer.injectScaledMaxHealth(CraftPlayer.java:2802) ~[luminol-1.20.4.jar:git-Luminol-"5579f65"]
  at net.minecraft.server.level.ServerEntity.sendDirtyEntityData(ServerEntity.java:400) ~[?:?]
  at net.minecraft.server.level.ServerEntity.sendChanges(ServerEntity.java:230) ~[?:?]
  at net.minecraft.server.level.ChunkTracker.foliaEntityTrackerTick(ChunkTracker.java:1099) ~[?:?]
  at net.minecraft.server.level.ChunkTracker.tick(ChunkTracker.java:1119) ~[?:?]
  at net.minecraft.server.level.ServerChunkCache.tick(ServerChunkCache.java:447) ~[?:?]
  at net.minecraft.server.level.ServerLevel.tick(ServerLevel.java:946) ~[?:?]
  at net.minecraft.server.MinecraftServer.tickChildren(MinecraftServer.java:1846) ~[luminol-1.20.4.jar:git-Luminol-"5579f65"]
  ... 6 more