Optionnally provide request HTTP headers to processors

[vprivat-ads]

Overview

Related Issue / discussion

This PR allows to forward request http headers to processors.

Our use case is to pass an API key to a processor.

Additional information

Dependency policy (RFC2)

• [x] I have ensured that this PR meets RFC2 requirements

Updates to public demo

• [ ] I have ensured that breaking changes to the pygeoapi master demo server have been addressed
  • [ ] https://github.com/geopython/demo.pygeoapi.io/blob/master/services/pygeoapi_master/local.config.yml

Contributions and licensing

(as per https://github.com/geopython/pygeoapi/blob/master/CONTRIBUTING.md#contributions-and-licensing)

• [x] I'd like to contribute feature X to pygeoapi. I confirm that my contributions to pygeoapi will be compatible with the pygeoapi license guidelines at the time of contribution
• [x] I have already previously agreed to the pygeoapi Contributions and Licensing Guidelines

[vprivat-ads]

@tomkralidis @webb-ben Should I rebase my work on top of #1902?

[github-actions[bot]]

This Pull Request has been inactive for 90 days. As per RFC4, in order to manage maintenance burden, it will be automatically closed in 7 days.

[github-actions[bot]]

As per RFC4, this Pull Request has been closed due to there being no activity for more than 90 days.