Add versioning support for git archives

[Saransh-cpp]

Given that we are using hatch-vcs (in both the project and the template), the following two files should be added in to support versioning from VCS for a user installing the project through a git archive -

• .git_archival.txt (example (can be copied entirely))
• .gitattributes (example (can be copied entirely))

[santacodes]

@Saransh-cpp does that apply only for hatch-vcs or also for setuptools config?

[Saransh-cpp]

Just saw this, for all vcs configs, independent of the backend.