Keys readme example does not run

[RickWinter]

The example needs to specifiy some options. We should look into the options and see if there should be default values.

use azure_identity::DefaultAzureCredential;
use azure_security_keyvault_keys::{models::KeyCreateParameters, KeyClient};
use azure_security_keyvault_keys::
    models::JsonWebKeyType;

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let credential = DefaultAzureCredential::new()?;

    let client = KeyClient::new(
        "https://<val>.vault.azure.net",
        credential.clone(),
        None,
    )?;

    // Create an RSA key.
    let body = KeyCreateParameters {
        kty: Some(JsonWebKeyType::RSA),
        key_size: Some(2048),
        ..Default::default()
    };

    let key = client
        .create_key("<key-name>", body.try_into()?, None)
        .await?
        .into_body()
        .await?;
    
    println!("Created key: {:?}", key);

    Ok(())
}