Add Minecraft pc 1.21.8 tags

[rom1504bot]

This automated PR sets up the relevant boilerplate for Minecraft pc version 1.21.8. Fixes (This issue was created for a minecraft-data-generator PR).

Related:

• Issue: (This issue was created for a minecraft-data-generator PR)
• Protocol Version: null
• Add TagsDataGenerator to supersede obsolete materials.json with modern tag system for multiple Minecraft versions minecraft-data-generator#56

• You can help contribute to this PR by opening a PR against this pc-1_21_8 branch instead of master.

[rom1504]

We would need a schema for the tags file

Also are we adding it only for 1.21.8 ?

[VasilisDragon]

Schema for the tags file proposed in #1194 — derived from and validated against this PR's tags.json (head 4edb806); all 5,417 block/item/entity_type members also cross-resolve against this PR's blocks.json/items.json/entities.json.