Tests: Copy the TZT reference test suite

Context

This MR copies the TZT reference test suite from the tezos/tzt-reference-test-suite repository to the tezos/tezos one.

The main advantage of hosting the tests on tezos/tezos is that it simplify testing in the CI both the Octez (see %Support for Michelson unit tests in TZT format) and Michelson-in-Rust TZT runners.

This MR does nothing about the tests but !4474 (merged) is stacked on this MR and uses the tests.

Manually testing the MR

Check that the files added by this MR correspond to the current master branch of https://gitlab.com/tezos/tzt-reference-test-suite/.

Checklist

• Document the interface of any function added or modified (see the coding guidelines)
• Document any change to the user interface, including configuration parameters (see node configuration)
• Provide automatic testing (see the testing guide).
• For new features and bug fixes, add an item in the appropriate changelog (docs/protocols/alpha.rst for the protocol and the environment, CHANGES.rst at the root of the repository for everything else).
• Select suitable reviewers using the Reviewers field below.
• Select as Assignee the next person who should take action on that MR