Remove hard dependency on Faraday

[andrewhavens]

Describe the idea
There is a hard dependency on Faraday. It is required within http_transport.rb which gets required automatically by transport.rb, even if you don't intend to use the HTTPTransport class.

Why do you think it's beneficial to most of the users
The SDK provides the ability to specify a custom transport (which was really helpful) but sort of defeats the purpose when you have a hard dependency that never gets used. There are also other http gems that people may be using and might not want to require additional http libraries.

Possible implementation
Either remove the hard dependency on requiring Faraday (call require as needed before initializing an http client). Or remove the hard dependency on requiring http_transport.rb.

[st0012]

Faraday is a critical component of the current implementation and it's risky to replace it with a lower level Net::HTTP implementation. So it's not at a high priority when rebuilding the new sentry-ruby SDK.

With that being said, we did receive a few complaints of requiring faraday. So I've listed it's removal in the Plan for version 5 a while ago 🙂

[mpeltomaa]

I have also depency issue with faraday

[iker-barriocanal]

Closing this issue since the request has been included in the plan for version 5.