Cauldrons do not use the "metal" sound for placement/breaking

Closely relates to MC-5991, as that ticket also concerned a metal block not sounding metallic.

The bug

Cauldrons are a block made of solid iron. As such, it'd be expected that they'd use the "metal" block sound. However, they instead use the slightly different "stone" sound.

How to reproduce

1. Place and break a block of iron, noting the sound it produces

2. Place and break a hopper, a block which, like the cauldron, is composed of iron, and is very visually similar, noting that it uses the same sounds as the block of iron

3. Place and break a cauldron, noting that it sounds a bit different

4. Place and break stone, noting that it has the exact same sound cauldrons used

Expected results

Cauldrons, being a solid iron block, would use the dedicated "metal" block sound type.

Actual results

Cauldrons just default to using the stone sound instead.

Notes

This was one of the cases listed in the invalid MC-91091. However, that ticket has since been split into many smaller tickets, which are themselves considered valid, and as such considering this to still be a duplicate of it would be unfair.