Mention that a new Auto DevOps pipeline will be created in the CI/CD > Pipelines empty state

(Idea from https://gitlab.com/gitlab-org/gitlab-ce/issues/43482#note_61937570)

Description

If you go to CI/CD > Pipelines, but no pipelines are there, an empty state is shown. It asks you to start with pipelines, but in case when Auto DevOps is enabled it is just a matter of pushing something in the repo.

Proposal

When a repo is empty and AutoDevOps is enabled, change the copy of the empty state for CI/CD > Pipelines, to inform users they just need to push something in the repo to start a pipeline.

There are currently no pipelines.

This repository is currently empty. A new Auto DevOps pipeline will be created after a new file has been pushed to a branch.