[CI] Add TRAVIS_COMMIT_RANGE variable
In order to optimize jobs, having the range of affected commits would be really useful. As the CI runner does not know all branches, and master
points to the wrong commit, calculating it ourselves is not possible.
Requested change
-
add CI variable comparable to TRAVIS_COMMIT_RANGE
The available CI variables do have CI_COMMIT_SHA
already, and mention CI_COMMIT_BEFORE_SHA
in one of the examples. CI_COMMIT_BEFORE_SHA
does not exist though.