settings: add updates settings extension

[sam-berning]

Issue number:

Closes #3649

Description of changes:

Adds an settings extension for updates settings

Testing done:

• Built aws-dev with the settings extension package included, spun up an ec2 instance with the resulting AMI.

• Updates settings (including the seed generated by bork) looked as expected

• /usr/libexec/settings/updates worked as expected:

bash-5.1# /usr/libexec/settings/updates proto1 generate --setting-version v1
{
  "Complete": {
    "seed": 722
  }
}
bash-5.1# /usr/libexec/settings/updates proto1 set --setting-version v1 --value '{"seed": 24, "ignore-waves": true}'

Terms of contribution:

By submitting this pull request, I agree that this contribution is dual-licensed under the terms of both the Apache License, version 2.0, and the MIT license.