Add a gcp_authorization flag to API methods

[jaketothepast]

Julia 1.5.0
HTTP.jl 0.9.12
MbedTLS.jl 1.0.3

I work for a company that uses GCP and Julia extensively. There currently is an aws_authorization flag, would anyone be open to adding GCP auth if possible? GCP is Oauth2-based authentication so I don't know if it is worth adding, it might be too much magic behind the scenes

[fredrikekre]

That functionality is beeing phased out (#486). You can probably use the same method that the AWS package now use for your usecase.

[jaketothepast]

Thank you for your reply, I figured that it would be removed in the near future,