fix: use linux/amd64 platform only for m1/m2 macs (arm64)

[k80bowman]

Description

When we migrated the container:push command to oclif/core, we added a --platform flag that would be passed to Docker. We set it to equal linux/amd64 because that would allow users using m1 or m2 Macs to push builds to Docker. However, that is causing problems for our users with older Docker applications that don't accept the --platform flag (#2967).

This PR adds logic that checks the user's architecture and then only adds the --platform flag if the architecture is arm64.

Testing

Tests require to have a valid Dockerfile to build images, you can use the example app from this Devcenter article, but the Dockerfile might require a change on the dependencies installation command, adding the flag --break-system-packages to the pip3 install command.

• Pull down this branch and run yarn && yarn build
• Navigate to the directory where your Dockerfile lives
• Start Docker if you haven't already
• Run <path_to_cli>/bin/run container:login to login
• Run <path_to_cli>/bin/run container:push. You may have to add a web or worker arg depending on your Dockerfile.