fix: restore adding http.url as an attribute when deprecated_attributes feature is enabled

[tl-thomas-finlayson]

• The SpanBackendWithUrl middleware used to add the http.url attribute which was migrated to the url.full attribute as part of https://github.com/TrueLayer/reqwest-middleware/pull/141 but was not restored along with the other deprecated attributes when the deprecated_attributes feature was added so this change is to add it back in if that feature is enabled

[swarmia[bot]]

✅  Linked to Story CONSOLE-1329 · [devx-admin-api] upgrade reqwest crates
➡️  Part of Epic CONSOLE-1322 · Client Console On-caller tasks