[GR-63591] Include resource bundles in resource configuration

[graalvmbot]

This PR moves the resource bundle registrations in reachability-metadata.json to the "resources" section. As a result, reachability-metadata.json files emitted by Native Image now contain only the "reflection" and "resources" sections.

Format
The format used is very similar to the previously used one, with the single difference being that the name of the bundle is given by the "bundle" field instead of "name", in order to be able to differentiate resource bundles from regular resources.
This change also formalizes the deprecation of "locales" (not needed since #9694) and "classNames" (supported through reflection) in the bundle definition object.
A resource bundle registration now looks like this:

{
    "resources": [
        {
            "bundle": "fully.qualified.resource.BundleName"
        }
    ]
}

Backwards compatibility
This change is fully backwards compatible. Registrations in the "bundles" section, in both reachability-metadata.json and resource-config.json files, are still parsed correctly and will be until this format is no longer used by the community.
This change will also be backported to the previous LTS versions of GraalVM in order for those to be able to parse reachability-metadata.json files emitted by Native Image from this point onwards.

Configuration merging
When merging configuration files, one of which contains resource bundle registrations in the previous format, all of them will be merged into a reachability-metadata.json file using the new format.