Breaking change, remove application settings deprecated fields

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Part of #6433 (closed)

• Removes field hashed_storage_enabled, removed in 14.0
• Removes field housekeeping_full_repack_period, use housekeeping_optimize_repository_period instead
• Removes field housekeeping_gc_period, use housekeeping_optimize_repository_period instead
• Removes field housekeeping_incremental_repack_period, use housekeeping_optimize_repository_period instead
• Removes field repository_storages, deprecated in 13.0, use repository_storages_weighted instead
• Removes conflicts from field housekeeping_optimize_repository_period as alternative fields now removed.