Release 1.6.0

[shuds13]

Pre-requisite:

• Release of gest-api.
• Merge of ASK/TELL DEVELOP #1307.
• Agreed naming of new functions/args (e.g. export / user_fields).
• Check dependencies - eg. docs/examples/ax_multitask.rst:Required: ax-platform_>=0.5.0 should be ==0.5.0
• Try Optimas generator directly in libEnsemble.
• How are gen_classes interfaces documented in libE / docs.

Release:

• Support for gest-api generators (plus selected generators provided in gest-api format).
• ibcdfo/jax example
• Removed Pydantic v.1 support
• Fix Shape error in GP_CAM ingest #1611
• Fix Required sim_id key in APOSMM #1612 (Needs to work with ingest - but we currently dont start remote gen until suggest).
• Fix CommFinishedException from APOSMM after initial evaluations are done #1613
• Provide appropriate _validate_vocs for APOSMM (inc. if does not take constants/constraints etc...)

See what else to include from #1350

Relevant but not the issue with #1612

• If aposmm.py needs _id should be specified - also the line entry["sim_id"] = entry.pop("_id") modifies incoming structure - setting of sim_id should be internal only. Can self.variables_mapping be used? E.g.:
  self.variables_mapping["sim_id"] = ["_id"]