Resolve "`--enable-feature` flag no longer works"
Raise an error if the release image name is invalid.
And check if release name starts with --
(and not just if it's equal to --
)
This allows us to use --enable-feature
again.
And in any other case where a release is expected, instead of an error like
`image': undefined method `[]' for nil:NilClass
We'll get:
$ gitlab-qa Test::Instance::Staging foo
...
The release image name 'foo' does not have the expected format. (Gitlab::QA::Release::InvalidImageNameError)
Closes #392 (closed)