Update dependency pipeline with image template and vhd copy

[eriqua]

Change

Closes issue #462

This change allows the creation of a custom image using Azure VM Image Builder in both the GH and ADO dependency pipelines.
In particular, the additional jobs are:

• deploying the Azure Image Builder template
• triggering the image build and waiting for its completion
• retrieving the location of the vhd file
• copying the vhd to a known storage account blob container as a dependency for compute/disks and compute/images modules

The custom image creation is optional in the dependency pipeline and disabled by default

Type of Change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update (Wiki)

Checklist

• I'm sure there are no other open Pull Requests for the same update/change
• My corresponding pipelines / checks run clean and green without any errors or warnings
• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation (readme)
• I did format my code