Fix shulkerboxes.sc 1.21 data components compability

[Senth]

Due to changes in data components, the shulker boxes script stopped working in 1.20.5/1.21. This PR makes shulkerboxes.sc compatible with 1.21 (and possibly 1.20.5, but I haven't tested it)

What changed

• Data components migration
  • Count is now lowercase count
  • Shulker inventory has been moved. BlockEntityTag.Items is now components."minecraft:container"
  • Custom data should be stored in components."minecraft:custom_data"
• Simplified some lines
• Consistency: Renamed variables to be more consistent across functions
• Formatting (remove trailing spaces, tabs were replaced with two spaces to be consistent with the rest of the file)

Testing (only tested in 1.21)

• [x] The following modes that were affected
  • [x] vacuum
  • 1 item
  • full stack
  • full stack where shulker has would be filled up, remaining should be picked up by the player
  • [x] restock same
  • [x] restock keep
  • [x] restock keep vacuum
  • [x] swap next
  • [x] swap same
• [x] Potions refills
• [x] Totem of undying

Note

I installed the vim plugin for scarpet, which reformatted the file, removing some trailing spaces. I can always split the PR into two if it needs to be more clear.

[lil-fox]

vacuum didn't work in pickup mode

[lil-fox]

mb, it work, but only if you have full stack, insted of work even vith one item, like in original