Support Build Flags

[coreybutler]

There doesn't appear to be a means of passing build flags. For example, docker build -t whatever . --no-cache doesn't seem to be possible right now.

[crazy-max]

@coreybutler All necessary build args will be available through build-push-action v2 (#92). You can already try it with:

• https://github.com/docker/setup-buildx-action
• https://github.com/docker/setup-qemu-action
• https://github.com/docker/login-action

[coreybutler]

Thanks @crazy-max!