automate gcloud components update

You're looking for the --quiet flag.

From gcloud --help:

 --quiet, -q
    Disable all interactive prompts when running gcloud commands. If input
    is required, defaults will be used, or an error will be raised.

This is generally a flag you'll want for non-interactive contexts.

You may also set the CLOUDSDK_CORE_DISABLE_PROMPTS environment variable to a non-empty value:

export CLOUDSDK_CORE_DISABLE_PROMPTS=1
gcloud components update # This works for all gcloud commands