Deploy loader.core v1.7 (elastic workers)

Contains:

• New configuration parsing to allow extra configuration override per fully qualified loader class name

Plan:

• Build images
  • swh-loader-savecodenow
  • swh-loader-package
  • swh-loader-git
• swh/infra/ci-cd/swh-charts!64 (merged): swh-charts: Adapt loader-git's default configuration for add-forge-now(-slow), loader-large
• swh-charts: Update image versions to deploy
• Deploy
• Checks
  • all loaders ok (impacted and non impacted)
  • ingestion on those origins is ok