get metadata from REST channel

[rgstephens]

Proposed changes:
@ancalita The REST channel should by default load the metadata key. I thought this worked in the past but can't seem to find when it was dropped.

Status (please check what you already did):

• added some tests for the functionality
• updated the documentation
• updated the changelog (please check changelog for instructions)
• reformat files using black (please check Readme for instructions)

[ancalita]

Good spot, I also couldn't find anything in closed PRs, docs or git blame, maybe it was never implemented 🤔
Could you please add a changelog entry and relevant test?

[rgstephens]

@ancalita do you know if this will be merged into the next 3.2.x release?

[ancalita]

@ancalita do you know if this will be merged into the next 3.2.x release?

I see this is targeting main actually, I'd recommend you rebase to 3.2.x and edit target branch on GH for the change to make it in the next micro release.

[rgstephens]

Closing this. Rebasing on 3.2.x and opening #11436.