Error Spam in console after island reset

[SkyDevil]

Description
A clear and concise description of what the bug is.
After Deletion of an island with the command /is reset
Console will start spamming

[18:00:38] [Server thread/WARN]: [BentoBox] Task #65 for BentoBox v1.6.0-SNAPSHOT-b1209 generated an exception
java.lang.NullPointerException: null
    at world.bentobox.bentobox.util.DeleteIslandChunks.regerateChunk(DeleteIslandChunks.java:84) ~[?:?]
    at world.bentobox.bentobox.util.DeleteIslandChunks.lambda$null$0(DeleteIslandChunks.java:53) ~[?:?]
    at java.util.Optional.ifPresent(Unknown Source) ~[?:1.8.0_211]
    at world.bentobox.bentobox.util.DeleteIslandChunks.lambda$new$1(DeleteIslandChunks.java:51) ~[?:?]
    at org.bukkit.craftbukkit.v1_14_R1.scheduler.CraftTask.run(CraftTask.java:81) ~[spigot.jar:git-Spigot-595711b-e8b39d4]
    at org.bukkit.craftbukkit.v1_14_R1.scheduler.CraftScheduler.mainThreadHeartbeat(CraftScheduler.java:394) [spigot.jar:git-Spigot-595711b-e8b39d4]
    at net.minecraft.server.v1_14_R1.MinecraftServer.b(MinecraftServer.java:1011) [spigot.jar:git-Spigot-595711b-e8b39d4]
    at net.minecraft.server.v1_14_R1.DedicatedServer.b(DedicatedServer.java:396) [spigot.jar:git-Spigot-595711b-e8b39d4]
    at net.minecraft.server.v1_14_R1.MinecraftServer.a(MinecraftServer.java:959) [spigot.jar:git-Spigot-595711b-e8b39d4]
    at net.minecraft.server.v1_14_R1.MinecraftServer.run(MinecraftServer.java:804) [spigot.jar:git-Spigot-595711b-e8b39d4]
    at java.lang.Thread.run(Unknown Source) [?:1.8.0_211]

This will continue even after a server reset however deleting the database fixes it.
Server seems to run fine after and the new island is created after the reset command
Steps to reproduce the behavior:
1.create and island
2. type /is reset twice
3 check console

Expected behavior
No errors in console

Server Information:

[tastybento]

I was able to replicate this by setting the use-own-generator setting to true. This makes the default generator become null and so you see these errors. Generally, this setting must be false. @SkyDevil what does your config.yml for BSkyBlock say?

Either way, this raises the issue that chunk regeneration is not supported in 1.14 onwards. So, although we can still allow use-own-generator, there will be no regeneration of chunks for deleted islands. We can work around it for BentoBox add-ons because we have a defined interface, but not for 3rd party plugins like CleanRoomGenerator. That Bukkit method (regenerateChunk) has gone! I'll change the config file to reflect this change.