restore_replace_* session settings

These settings are available in system.settings and are autogenerated from source.

restore_replace_external_dictionary_source_to_null

Replace external dictionary sources to Null on restore. Useful for testing purposes

restore_replace_external_engines_to_null

For testing purposes. Replaces all external engines to Null to not initiate external connections.

restore_replace_external_table_functions_to_null

For testing purposes. Replaces all external table functions to Null to not initiate external connections.