[26.2] fixed shearing sulfur cubes with custom shears

[cech12]

This PR fixes shearing sulfur cubes with custom shears. Interacting with sulfur cubes containing a block didn't result in shearing off the block as vanilla shears.

I reused the tool action SHEARS_HARVEST, because I don't think an extra tool action for handling sulfur cube shearing is necessary.

I also added a corresponding automated test.

[LexManos]

Overall looks good/simple enough.
Only thing I can think of is needing to adapt things to properly override the IForgeShearable.onSheared function
When I get back to a computer i'll run the test/pull. Unless someone runs the test before me.

[LexManos]

Okay, back at a computer, reviewing the whole IForgeShearable system.
Looks like it cam be completely be removed in favor of Vanilla's Shearable interface for Entities.
For breaking Blocks, you can use a loot table with a shears condition like we do for the vanilla blocks.
For use on Blocks, or BlockEntites you can use Block.useItemOn

26.2...MinecraftForge:MinecraftForge-Experimental:shears

If there is no major object to this I can do so.

[autoforge]

@cech12, this pull request has conflicts, please resolve them for this PR to move forward.