instrumentation-http: Parse URL instead of relying on pathname

[whs]

instrumentation-http rely on options.pathname for outgoing request to name the span. However, several libraries are passing options directly to http.request which save it as is.

Affected libraries include:

• node-fetch 1.x.x (can be solved by upgrading to 2.x.x)
• request

To reproduce, simply setup a tracer and fire an outgoing request with request. The trace will have the name of GET undefined.

This PR ensure that we parse every option for pathname instead of relying that it exists.

[OsvaldoRosado]

Marking as request changes to remove the "review required". Looks good to me other than the comment I left to ensure compatibility with existing options.pathname when missing options.path.

[whs]

Fixed, please check