Support profiling queries via tracing

[iskakaushik]

Adding support for tracing via https://docs.rs/tracing/latest/tracing/ would be useful. Given that most of the requests are going through reqwest, seems like https://github.com/TrueLayer/reqwest-middleware might be a good candidate.

Let me know if this is something that you think will be generally useful and I'm happy to submit a PR for this. This can be behind a cargo feature, maybe profile, that way it can be enabled only when profiling.

Thanks for the awesome crate.

[lquerel]

Thanks for the suggestion and I agree that adding a tracing capability would be helpful. Please submit a PR with an implementation of your proposal. Regards, Laurent