BS-9391 : [6.3] Size of documentcontentmimetype column in document_mapping table is incompatible with the RFC

- Add migration
BS-9391 : [6.3] Size of documentcontentmimetype column in document_mapping table is incompatible with the RFC

- Fix bad SQL scripts for Postgres & Oracle
Merge branch '6.3.x' into 'MasterBugFixing'