[#902] Deprecate OPEN_CHEST

Discussion point: the fact of the matter is, despite what the tezos changelog says, chest_key and chest types are also deprecated. However, we don't have a mechanism to deprecate those in morley. I don't really think we need one, and we can just leave things be, but I'm open to suggestions.

UPDATE: types are explicitly "banned" in 0b5f2490, but arguably that is a giant ugly hack.

Description

Problem: In Lima, OPEN_CHEST is deprecated.

Solution: Do likewise in our code. Additionally, forbid typechecking OPEN_CHEST instruction and chest and chest_key values in strict tc mode.

NB: AnnOPEN_CHEST and untyped OPEN_CHEST are purposefully left un-deprecated to avoid proliferation of -Wno-deprecations everywhere. The rationale is that untyped OPEN_CHEST needs to be typechecked, and that will fail in strict mode, and AnnOPEN_CHEST is not intended to be user-facing, so it's assumed the user knows what they're doing if using AnnOPEN_CHEST directly.

Related issue(s)

Resolves #902 (closed)

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