Use dockerfile build args correctly, respect context path, fix image aliasing

[KyleBarton]

Self-Review Checklist:

• I've reviewed my own diff for quality, security, and reliability
• Unsafe blocks (if any) have justifying comments
• The content is consistent with the UI/UX checklist
• Tests cover the new/changed behavior
• Performance impact has been considered and is acceptable

Closes #54193

Additionally, respects cacheFrom and options args defined in devcontainer.json's build object. Also, addresses a bug which was hiding these problems by overriding the primary build target with aliasing.

Release Notes:

• Fixed an image aliasing but, respect build context and build args in dev containers