Air replacement in caves not working

Prerequisites

• I am running the latest alpha version of Structurize for my Minecraft version.
• I checked the MineColonies/Structurize wiki and made sure my issue is not covered there.
• I made sure that this issue is not a duplicate of any existing issue.

Context

• Minecraft Version: - Structurize Version:
  MineColonies Version (if related bug): minecolonies-0.14.9-ALPHA-universal.jar
• Related Mods and their Versions: structurize-0.13.148-ALPHA-universal.jar (was given the okay to post this issue regardless of the slightly old version over on the discord https://discord.com/channels/139070364159311872/493961385034776607/820054558986338376)

Expected behavior

Select an area with the scan tool that is in a (natural) cave area, and try to replace the Air blocks with another block. The new block replaces all of the air blocks.

Actual behavior

Nothing is replaced.

Steps to reproduce the issue

1. Select an area with the scan tool that is in a (natural) cave area
2. try to replace the air blocks
3. see if it works
4. (related to note)
   4a. select same area with world edit tool
   4b. type //count air and see what it says
   4c. type //count cave_air and see what it says
   4d. See if the cave_air is the blocks that aren't being replaced (if some were replaced but not all by the scan tool)

Notes

I did a count of the blocks in the same selected area using world edit, and it's counting 0 blocks of air, but many blocks of cave_air. This is likely just overlooking cave_air being air or something along those lines.

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