Version: Create sub-library Tezos-version.Value

Context

This merge request is a preliminary work toward reducing the number of opam packages.

It suggests to create a sub-library tezos-version.value of tezos-version. This sub-library depends on universe to generate generated_git_info. Thus, tezos-version won't depend on universe.

This would allow octez-version to be included in a octez-libs (see !8637 (merged)) library whitout needing this to depend on universe.

Manually testing the MR

• make -C manifest/
• make

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