Don't skip ci to pass ci #22

The Gotenna Pro challenge currently skips execution if the device string is not for a bladerf or uhd device, which effectively skips over the ci test. The bladerf flowgraph for the Gotenna Pro challenge uses an osmocom sink, which supports the /dev/null devices that we use for ci, and should also support other device types that are supported by osmocom.

Test and update the Gotenna Pro challenge to use the osmocom sink flowgraph for all supported devices to simplify the challenge, and to enable ci to work properly.