This partially reverts commit d7321893.

The *.jar files are not being built and all Debian builds are failing
as dh_install stops on missing files. To build them we would need to also
add new Java build dependencies.

In a stable release (10.2->10.5) we shouldn't add new files and certainly
not any new build dependencies, so reverting commit.

Also, the files are located in a different path, and already included
in the mariadb-test-data package:

  /usr/share/mysql/mysql-test/plugin/connect/connect/std_data/JavaWrappers.jar
  /usr/share/mysql/mysql-test/plugin/connect/connect/std_data/JdbcMariaDB.jar
  /usr/share/mysql/mysql-test/plugin/connect/connect/std_data/Mongo2.jar
  /usr/share/mysql/mysql-test/plugin/connect/connect/std_data/Mongo3.jar

This change needs to be redesigned and applies only on 10.6 or newer.