feat: migrate GCP account and update cluster

[agaudreault]

This PR migrates the stack the cluster to a new GCP account.

Current account owners: @leoluz and @agaudreault

Changes:

• Add infrastructure as code for the GCP account
• Update several apps
• Remove jenkins app
• Add external-dns to manage the new apps.argoproj.io zone.

Future work

• Some configurations are added manually, mostly secrets (https://github.com/argoproj/argoproj-deployments/issues/29)
  • Use SealedSecrets to manage the secrets as code
• argoproj.io DNS zones need to be migrated to the new GCP account and added to the infra as code. (https://github.com/argoproj/argoproj-deployments/issues/30)
  • Need to move all records outside of apps.argoproj.io, and ultimately infrastructure serving it.
  • The domain needs to be configured accordingly. This will require more sync with the CNCF
• Current admin team config from argoproj is outdated so admin cannot login with the Github auth. (https://github.com/argoproj/argoproj-deployments/issues/31)
  • Need to create/update the admin team in https://github.com/orgs/argoproj/teams.
• Applications are applied manually in the cluster. (https://github.com/argoproj/argoproj-deployments/issues/32)
  • The apps-of-apps pattern could be used
• Infrastructure as code has a user-access module to explicitly define the permissions. This gives permissions to users based on their personal gmail. Some concerns have been raised about having this information in the code. (https://github.com/argoproj/argoproj-deployments/issues/33)
  • Use a data source that will hold the users emails or use google groups
• Migrate all other resources and delete old project (https://github.com/argoproj/argoproj-deployments/issues/34)
  • Before deleting the old GCP project, all resources needs to be migrated to the infra as code
• CI pipeline to detect terraform change
• Add more documentation on how to maintain/update the infrastructure and the different components
• Need to update codeowners to review infrastructure changes
  • Create a github team?