Add multi-arch support

[nwhobart]

Expected Behavior

• Running the docker run command w/o getting a warning or running in emulation

Current Behavior

• When running the image on an M1 Pro MacBook Pro:

WARNING: The requested image's platform (linux/amd64) does not match the detected host platform (linux/arm64/v8) and no specific platform was requested

Possible Solution

• Build for multi-arch using docker buildx

Steps to Reproduce (for bugs)

1. On an M1-based Mac run the suggested Docker command on current image.

Context

• many folks will be using M1 Macs in the future

Your Environment

• App Version used: 2.4.3
• Operating System and version: M1 Pro macOS 12.0.1