Remove the "Job dependencies view" promotion/ feature feedback banner from the pipeline page

Problem

With the release of the job dependencies view in the pipeline graph we released a dismissable banner to promote the feature and gather feedback on it. The banner can be a bit disruptive to one's workflow, so it should be turned off once it's purpose has been realized.

Proposal

Now that we've been gathering the feedback on it for more than a month we should consider turning off that banner soon as it's not necessary for new users, it was only meant to advertise the feature to current users and to gather initial feedback.