dont compute git info when not cloud not enabled and warn message improvement

[tongueroo]

This is a 🐞 bug fix.

• [ ] I've added tests (if it's a bug, feature or enhancement)
• [ ] I've adjusted the documentation (if it's a feature or enhancement)
• [x] The test suite passes (run bundle exec rspec to verify this)

Summary

Don't compute vcs info when terraspace cloud is not in use. Also provide a user a warning when unable to get info from local git repo.

Context

Closes #254

How to Test

Sanity test

Version Changes

Patch

[tongueroo]

Released in 2.1.5