This commit removes the deprecated Map-based job repository
and job explorer implementations with their respective DAOs.
Using the `EnableBatchProcessing` annotation now requires a
datasource bean to be defined in the application context.
This will be reviewed as part of #3942.
This commit is a first pass that updates related tests to use
the JDBC-based job repository/explorer with an embedded database.
A second pass should be done to improve tests by caching/reusing
embedded databases if possible.
Issue #3836
f8bdf5521e