Update publish fix

Cleanup for publish step:

• Moving wall of variable declarations into repo_map_vars.sh
• Updating create_repo_map.py to handle checking for existing repo_map.json in S3, rather than a separate curl command
• Moving other exported variables to the variables: list, removing unnecessary export command
• Directly referencing environment variables sourced from repo_map_vars.sh in create_repo_map.py new_data json struct to avoid the need to feed every argument to the script and processing.