examples/get_profiles should be updated to use account().fetch_user_profile

[Half-Shot]

If only because it would save the next person a hour researching into the 401 errors when using Synapse with reasonably hardened configs, ultimately caused by https://github.com/matrix-org/matrix-spec/issues/2254 and https://github.com/ruma/ruma/issues/380.

[zecakeh]

It seems like the purpose of this example was to demonstrate how to make an arbitrary request with Client::send(): https://github.com/matrix-org/matrix-rust-sdk/commit/7201749280c06092cdc176cc9c83506c854d8af1. Maybe the example should be changed to make a request to a different endpoint instead?