Many, if not most, useful timescaledb hyperfunctions require timescaledb-toolkit which is included in their managed offering.
It would be great for the timescaledb image to include it. Currently this requires building a custom image which is not ideal.

Fortunately it is quite easy to add via a Debian package and available on the packagecloud timescale repository

The Enabling TimescaleDB docs should also note enabling/updating the extension