Add optional HTTP post options

[micwiec]

@johnsusek Can you add in HTTP POST UI option to define http_post_static_payload?

In ElastAlert YAML it might like this:

[...]
http_post_static_payload:
    error_id: XYZ_123
    error_description: "There is a problem with XYZ."

ElastAlert Doc: https://elastalert.readthedocs.io/en/latest/ruletypes.html#http-post

[Sinistr0]

Any predictions when the http_post_ static payload option will be added?

[nsano-rururu]

No plans to support