CI should throw an error if ``CI_BRANCH_TO_TEST`` is not found in any of the repos

[adityapande-1995]

Currently, the CI does not throw an error an continues with the default branches if CI_BRANCH_TO_TEST is not found in a repo. However, if it is not found in any of the repos, an error should be thrown.

This would help in a case when someone misspells a branch name, or tries to run CI on a branch that exists on a fork of a ROS repo.