docs: attributes undocumented for certain logging plugins

[Gallardot]

Current State

Thanks to APISIX's excellent design, I found that many logging plug-ins support features such as include_req_body, include_req_body_expr,include_resp_body,include_resp_body_expr, such as file-logger,http-logger,loggly,tencent-cloud-cls. However, this feature does not appear in the plug-in documentation or in the plug-in schema definition.

Desired State

Maybe we should add the above.

[Neilblaze]

@Gallardot I'm taking this up!

[pottekkat]

@Neilblaze Are you still working on this issue?

[Neilblaze]

@navendu-pottekkat Sorry for the delay. I'm working on another issue, so if anyone wants to pick this up, please feel free to assign :)

[smileby]

@kayx23 can assignees it to me. I'll do it

[pottekkat]

@smileby Thank you. Assigned.

[kayx23]

Going through some logging plugins now and noticed these options are not added to all logging plugins, such as google-cloud-logging and splunk-hec-logging. Should we open a new issue and track progress of the remaining, if any needs? Open for discussion.