Add allen-hmba-releases.yaml to datasets folder

[Bl4ckH4wkGER]

Issue #, if available:

Description of changes:
Register new allen-hmba-releases bucket with AWS OpenData

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[berylrab]

Hi @Bl4ckH4wkGER, have you submitted an application for this dataset already? If not, please apply here: https://application.opendata.aws/

[Bl4ckH4wkGER]

Hi @berylrab ,
This is part of Allen Institute's overall Open Data agreement. Jon Martin on your side should have further details as needed.

Please let me know if a separate application is still required. FWIW, we plan to add dedicated tutorial resources etc over the next few months once the paper pre-prints and final publications get published.