Update Readme

[mfarina1]

The following updates need to be made to the Readme sooner rather than later:

• We mention APLNIS (and its root CA) in the Readme, this should be removed
• "To start the system in the future, use..." under "Quickstart" => what does that even mean? Need to elaborate
• "Build test environemnt images" typo under "Manual startup" section
• In troubleshooting section, add note about "external volume "sockdir" not found" error when running docker compose up -d (because sockdir is marked as external in our docker-compose.yml file)
• Also in troubleshooting section, add note about how if it takes you straight to the ANMS GUI and doesn't ask you to log in with the admin creds, this means you're on the wrong port
• Check for and resolve any other typos
• Check for and resolve any other confusing phrases
• IMPORTANT: add caveat about how Podman/Docker versions are not always backwards compatible, and one should refer to Product and User Guides for test environment description and the exact version numbers (or just include those versions in the Readme directly)