iohkNix env cleanup, byron-to-alonzo script updates

[johnalotoski]

Description

• Makes the set of 8 scripts/byron-to-alonzo/*.sh work again with current node/cli versions
• Removes from configuration/cardano the deprecated shelley_qa configurations
• Adds to configuration/cardano the iohkNix testnet-template configurations
• Updates the configuration/cardano/update-config-files.sh script to reflect these changes
• Switches the byron-to-alonzo scripts to utilize testnet-template config instead of shelley_qa
• Updates workbench to remove a legacy testnet dependency
• Bumps iohkNix for a similar environment cleanup and updates CI to match
• Removes remaining repo references to deprecated envs such as sanchonet, shelley_qa and (legacy) testnet

Checklist

• Commit sequence broadly makes sense and commits have useful messages
• CI passes. See note on CI. The following CI checks are required:
• Self-reviewed the diff