(build-tools): base command with build project context

[zhenmichael]

BaseCommandWithBuildProject class inherits existing BaseCommand class. Provides alternative to existing Context class which uses BuildProject from the build-infrastructure package instead.

This new base command is to be used to re-implement existing commands.

[alexvy86]

I'm curious about the motivation or use case for the whole change, if it requires us to make this public and get it published.

[tylerbutler]

Great question. The ultimate goal is to replace all of the release group/package handling code in build-cli commands with the new code from build-infra. But rolling out changes to all the commands at once is just too big a change/task, so the plan is to convert commands one-by-one by creating new versions of the commands that use this new base class. That way we can roll out the changes piecemeal.

Long-term, we may not need a separate package for the infra stuff, but at the moment it's much easier for it to be separate right now, because build-cli and fluid-build need the underlying code. Unfortunately, fluid-build cannot depend on build-cli today because there's already a dep going the other way (that is, build-cli depends on fluid-build).