databases/speedtables: update to 1.9.2

Changelog:
https://github.com/flightaware/speedtables/compare/v1.9.0...v1.9.2

Release notes:
https://github.com/flightaware/speedtables/releases/tag/v1.9.1
https://github.com/flightaware/speedtables/releases/tag/v1.9.2