APISIX should not forward client API key to upstream?

[aaltonja]

Verify whether wanted or not.

Assuming no then:

there is branch drop-client-apikey-from-proxy-req in api-management-tool-poc repo that has fix "hide_credentials": true.

TODO: Verify what happens if GW and upstream uses exactly the same name for api key used between their communication bbecause that api key should not be dropped.