[Features] addon should support air-gapped environment delivery configuration

[ldming]

What is the user interaction of your feature

KubeBlocks should support to install on the air-gapped environment, so addon should support to set private helm registry.

Now, addon has already supported to set private helm registry by addonChartLocationBase, but the registry MUST allow anonymous read. Addon should support to access registry using password and username.

[nashtsai]

just "addon should support to access private helm registry with password" is not a feature, I would say "support air-gapped environment delivery configuration" is a feature, and for this requirement I would suggest provide self-bootstrap chart tgz delivery to fullfil the requirement.

[ldming]

I will build an image that contains all dependency helm charts, addon Job will copy these helm chart in initContainer, the job use these helm charts to install.

[ldming]

Had been supported.