lua: Allow to set header entry as table to httpCall and respond APIs

[dio]

Description: Extends httpCall() and respond() APIs to accept headers with values that can be strings or table of strings.

Risk Level: Low
Testing: Modified the existing unit tests
Docs Changes: Added
Release Notes: Added
Fixes #7742

Signed-off-by: Dhi Aurrahman dio@tetrate.io

[dio]

@mattklein123 do we want to return header values of the same header entry key as a table when we do headers:get() as well, should it be filtered for non-":" and predefined headers?

[mattklein123]

@mattklein123 do we want to return header values of the same header entry key as a table when we do headers:get() as well, should it be filtered for non-":" and predefined headers?

I'm concerned this might break existing scripts? WDYT? Perhaps we don't do it for now or provide some type of API ability to return it this way?

[mattklein123]

@dio please let me know when this is no longer WIP. Thank you!

/wait

[dio]

@mattklein123 yes, think this is ready for review. Thank you!

While for getting multiple values from a header name can be done via :pairs for now.

[mattklein123]

LGTM with small nit. Thank you!

/wait

[dio]

Oops. Accepting suggestion hurts DCO. Did force pushing. Sorry.

[mattklein123]

LGTM post security release