Variable check for .gitlab-ci.yml
Description
Implement a check to ensure that variables defined inside .gitlab-ci.yml
are populated. Currently, the pipeline will run with the empty value.
Proposal
Could be similar to the yaml check that is currently in place. Throw a warning and fail the pipeline when a variable does not have a value.
Links / references
Customer ticket -> https://gitlab.zendesk.com/agent/tickets/91604 (internal)