ANTS upgraded to Iris 3.7

[hdyson]

Core ANTS trunk and contrib trunk have now both been updated for compatibility with iris 3.7 and mule 2023.08.1 (and corresponding updates to dependencies). This is a key activity to align regular ANTS with ongoing NGMS UG-ANTS work at the ANTS 2.0 release.

If there are any unexpected issues, please let us know either here or at miao@metoffice.gov.uk.

For tickets in progress, new branches from head of trunk are likely to be needed to ensure the rose stem tests pass (bear in mind that the rose stem tests are run as part of the code review).

There are no current plans for more changes to dependencies before the ANTS 2.0 release: https://code.metoffice.gov.uk/trac/ancil/wiki/ANTS/SteeringGroup/ReleaseSchedule#ANTSreleaseschedule