Fixes https://github.com/payloadcms/payload/issues/12776
- Adds a new `jobs.config.enabled` property to the sanitized config,
which can be used to easily check if the jobs system is enabled (i.e.,
if the payload-jobs collection was added during sanitization). This is
then checked before Payload sets up job autoruns.
- Fixes some type issues that occurred due to still deep-requiring the
jobs config - we forgot to omit it from the `DeepRequired(Config)` call.
The deep-required jobs config was then incorrectly merged with the
sanitized jobs config, resulting in a SanitizedConfig where all jobs
config properties were marked as required, even though they may be
undefined.
769ca03bff