Deploy new Go binaries automatically using goreleaser and google cloud build

[jjbuchan]

Go releaser automation builds go binaries for several different platforms.

There are specific instructions for setting this up for google cloud build.
https://goreleaser.com/ci/#google-cloudbuild

• Generate a github personal access token with the following permissions:
  repo:status Access commit status
  repo_deployment Access deployment status
  public_repo Access public repositories
• Save the personal access token (will later encrypt this using KMS)
• setup a keyring and key using the following instructions https://cloud.google.com/cloud-build/docs/securing-builds/use-encrypted-secrets-credentials
• using gcloud tool you can encrypt the token using the following example

echo -n $MY_SECRET | gcloud kms encrypt \
  --plaintext-file=- \  # - reads from stdin
  --ciphertext-file=- \  # - writes to stdout
  --location=global \
  --keyring=[KEYRING-NAME] \
  --key=[KEY-NAME] | base64