refactor: update task definitions and environment setup for food catalog sample

[garrytrinder]

Merging this PR will update the nodejs-typescript-food-catalog sample:

• We now have two stages in the YAML file instead of one
  • Provision
    • Ensures Azure Functions Core Tools v4 are installed
    • Executes npm install
  • Deploy
    • Contains the original tasks
• Early exit if Dev Tunnels CLI is not installed
  • We ensure the env files, then run the Dev Tunnels script before anything else
  • If CLI is not installed, the whole process stops and a message is shown with a link to docs with install info in the terminal output
• After ensuring the Dev Tunnel
  • We run the tasks in the Provision stage in YAML file
  • We start the Azurite service
  • We run the tasks in the Deploy stage in YAML file
• Fixes issue where NOTIFICATION_DOMAIN env var was not being created
• Tasks are no longer executed if the previous task in the sequence fails