/usr/lib/ruby/vendor_ruby/rails/generators/rails/app/templates/config/databases/ is in ruby-railties 2:4.2.6-1.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/ruby/vendor_ruby/rails/generators/rails/app/templates/config/databases/frontbase.yml
/usr/lib/ruby/vendor_ruby/rails/generators/rails/app/templates/config/databases/ibm_db.yml
/usr/lib/ruby/vendor_ruby/rails/generators/rails/app/templates/config/databases/jdbc.yml
/usr/lib/ruby/vendor_ruby/rails/generators/rails/app/templates/config/databases/jdbcmysql.yml
/usr/lib/ruby/vendor_ruby/rails/generators/rails/app/templates/config/databases/jdbcpostgresql.yml
/usr/lib/ruby/vendor_ruby/rails/generators/rails/app/templates/config/databases/jdbcsqlite3.yml
/usr/lib/ruby/vendor_ruby/rails/generators/rails/app/templates/config/databases/mysql.yml
/usr/lib/ruby/vendor_ruby/rails/generators/rails/app/templates/config/databases/oracle.yml
/usr/lib/ruby/vendor_ruby/rails/generators/rails/app/templates/config/databases/postgresql.yml
/usr/lib/ruby/vendor_ruby/rails/generators/rails/app/templates/config/databases/sqlite3.yml
/usr/lib/ruby/vendor_ruby/rails/generators/rails/app/templates/config/databases/sqlserver.yml