[Chore] Add missing FromExpression conversions

Description

Problem: In #696 (closed) we've added chest and chest_key types. However, one conversion for those types is missing.

Solution: Add the missing conversion. Also add the types to cleveland generators.

Related issue(s)

I've eschewed creating an issue for this, it's a very straightforward minor fix.

Checklist for your Merge Request

Related changes (conditional)

• Tests (see short guidelines)

  • If I added new functionality, I added tests covering it.
  • If I fixed a bug, I added a regression test to prevent the bug from silently reappearing again.

• Documentation

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    • Root README and other README.md files
    • Haddock
    • docs/
  • I updated changelog files of all affected packages released to Hackage if my changes are externally visible.

I don't know if it's worth mentioning in the changelog.

Stylistic guide (mandatory)

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code/morley/CHANGES.md

 <!-- Unreleased: append new entries here -->
 
+* [!1040](https://gitlab.com/morley-framework/morley/-/merge_requests/1040)
+  Add missing `FromExpression` conversions
+  + `Chest` and `ChestKey` cases were missing in `FromExpression` conversions.
+
 1.16.1
 ======
 * [!1016](https://gitlab.com/morley-framework/morley/-/merge_requests/1016)