Drop daily pipeline since we got rid of hawkBit

We completely decommissioned hawkBit last December, but it has not been in use for a longer while.

The scheduled pipeline is actually failing with an error, but it is not being captured:

curl: (7) Failed to connect to hawkbit.apertis.org port 443 after 4 ms: Couldn't connect to server

See https://gitlab.apertis.org/infrastructure/apertis-infrastructure/-/jobs/3206736 and https://phabricator.apertis.org/T9870.