Change Command/Thunk.hs to nix-thunk package

[romefeller]

Include nix-thunk package to enhance thunking tools.

I have:

• Based work on latest develop branch
• Followed the contribution guide
• Looked for lint in my changes with hlint . (lint found code you did not write can be left alone)
• Run the test suite: $(nix-build -A selftest --no-out-link)
• Updated the changelog
• (Optional) Run CI tests locally: nix-build release.nix -A build.x86_64-linux --no-out-link (or x86_64-darwin on macOS)

[plt-amy]

This is blocked on obsidiansystems/cli-nix#3 ATM which is blocked on a new release of cli-extras

[plt-amy]

The force pushes above are because I accidentally ran the self-test commands in the obelisk directory so we had two commits from Obelisk Selftest. That was embarrassing. This upcoming one is a rebase

[madeline-os]

Minor changes requested; some administrative stuff I am putting on you :3

[alexfmpe]

Something changed in this PR that changed the 'clear console on code recompilation' behavior of ob run - noticed this while running ob run on the skeleton on current develop.
The new behavior is present on the commit which acted as merge for this PR, but not in its mainline parent, 17d0277

Old

New

[alexfmpe]

ob shell seems to have been broken by this change. After this PR, ob shell doesn't actually drop me into a nix shell anymore.