Extend backup and restore creators to include configuration

[moogacs]

the backup and restore endpoints now offers compression configuration to be adjusted by the endpoints like Compression level, CPU percentage, Chunk size

see new spec.

• BackupConfig
• RestoreConfig

would like to extend the client to make that config available from the client side, so that users would be able to configure their backup and restore

linked to https://github.com/weaviate/weaviate-go-client/issues/208