Platform Tests should run on different DB than H2

Right now, the Platform Tests run against H2, which is not used in production.

We want the tests to run on PostgreSQL & My SQL in addition to H2. i.e. CI plan where these tests are run against both MySQL and PostgreSQL.

We've had some bugs in the Front End because the software was trying to use MySQL DB, but was not called by H2 DB. 

Requested by Daniel Kayiwa.