Pull docker version from docker hub

[brent-hoover]

When you create a new project-api the docker file that is used from the project template has a hardcoded reaction version. It should pull whatever is the the latest version number at the time of project creation from docker hub and use that instead. For deterministic builds we DO NOT want to use :latest

[skodamarthi]

@zenweasel Can I work on this? Do you want it to be pinned to the latest version of reactioncommerce/reaction?

[rum1887]

@zenweasel is the issue still open? for hacktoberfest 2023