new: support token http header

[eidam]

Hi! 👋 I would love to use HTTP state backend with JWT tokens. This PR adds support to optionally pass token http header to the http backend. (POC https://twitter.com/adam_janis/status/1452389074812260359)

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[crw]

Thanks for the PR! We will take a look at reviewing this for a future release.

[crw]

Thanks again for this submission! The reason it has not been reviewed is due to the general hold on backend reviews (see CONTRIBUTING.md#state-storage-backends. I will update this PR if/when that is lifted. Thanks for your patience!