Previously, DatabasePopulatorUtils#execute looked up a Connection from
the given DataSource directly which resulted in the executed statements
not being executed against a transactional connection (if any) which in
turn resulted in the statements executed by the populator potentially
not being rolled back.
Now DataSourceUtils#getConnection is used to transparently take part in
any active transaction and #releaseConnection is used to ensure the
connection is closed if appropriate.
Issue: SPR-9465
Backport-Issue: SPR-9457
Backport-Commit: 49c9a2a915