chore: modify dockerfile to build with stbernard

[superlinkx]

Description

This PR updates the existing Dockerfile to build with stbernard instead of beagle. A few key changes were necessary to enable this functionality:

• Pulling the version from the environment variable if the git tag was unavailable. This was necessary to support building the edge release.
• Adding flags to override the GOOS and GOARCH environment variables. This enables stbernard to build against any environment via go run. Prior to this change the variables would conflict against the architecture that was calling go run stbernard.

Also included in this PR is the removal of Python from the Docker build as it was only used by beagle.

Motivation and Context

• Consolidate on a single CLI tool for BloodHound

How Has This Been Tested?

• Ran the builds locally and on GitHub actions and verified they built successfully

Screenshots (if appropriate):

Types of changes

• Chore (a change that does not modify the application functionality)
• 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 change)

Checklist:

• Documentation updates are needed, and have been made accordingly.
• I have added and/or updated tests to cover my changes.
• All new and existing tests passed.
• My changes include a database migration.

[superlinkx]

The only one of these suggestions I'm really worried about is the potential panic, otherwise these are minor suggestions that can be either changed or resolved as wontfix. Overall this looks really good and I appreciate getting this plumbed in properly.

[superlinkx]

Thanks for all the updates, looks good to me

[zinic]

LGTM, pull!