Implemented a `TargetApi` enum to make the process of implementing
tests for the D-Bus and HTTP API more convenient.
Refactored `test_api_{create_boot, shutdown, pause_resume, delete}` tests
with the `TargetApi` enum to also implement tests for the D-Bus API.
Added a new test named `test_api_dbus_and_http_interleaved` that uses
both the HTTP and D-Bus API at the same time.
Modified integration test scripts to enable the `dbus_api` feature when
compiling and start a dbus-session when integration tests are run.
Signed-off-by: Omer Faruk Bayram <omer.faruk@sartura.hr>
a7aecb5eee