fix: if db_type is not defined then set default to 'mariadb'  (bp #11346) (#11348)
fix: if db_type is not defined then set default to 'mariadb'  (bp #11346) (#11348)

Co-authored-by: Saurabh <bcd7ed50b563770ca2428ef4d00b0eb1d7ef83b8@erpnext.com>
vjFaLk/frappe,vjFaLk/frappe,vjFaLk/frappe,vjFaLk/frappe