fix: pinned docker-cpi version

[mike-jc]

Summary

1. Pinned the Docker-CPI image to the workable version (Bosh v282.1.13).

• This image is currently actively developed, and periodically, some bugs and/or breaking changes are introduced, causing the acceptance tests to fail. The bugs are fixed in future versions, but in the meantime, we are blocked.
• Previously, we always used the image with the tag latest. Unfortunately, there are no release-like tags with stable versions, so I have chosen the latest version that passed the tests.

2. Changed resource type for Docker CPI to registry-image.

• The resource type docker-image does not support pulling images by digest.

3. Added the missed triggers to automatically rerun tests when the haproxy-boshrelease image changes.

[mike-jc]

Closed in favor of #929