[v9] Set `spans: false` in `httpIntegration` when `skipOpenTelemetrySetup: true`

[lforst]

Description

Details outlined in #14660 (comment)

[mydea]

Just leaving this here, from some offline discussion: We may do it this way, or some other way - basically, the intent is that for people that disable otel instrumentation, ideally we do not register the HttpInstrumentation by default. How exactly we make this happen, is a bit up for debate...

[mydea]

For reference, in node-fetch we actually do this automatically - there is no spans option, if tracing is disabled we simply do not emit spans. We could think about doing the same thing for the httpIntegration, so basically get rid of spans option - it was done this way in http because we added this later, so we could not break the behavior of this...