Fix incorrect async usage on client_credentials_for_provider

crates/handlers/src/upstream_oauth2/callback.rs

@@ -294,8 +294,7 @@ pub(crate) async fn handler(
         lazy_metadata.token_endpoint().await?,
         &keystore,
         &encrypter,
-    )
-    .await?;
+    )?;
 
     let redirect_uri = url_builder.upstream_oauth_callback(provider.id);
 

crates/handlers/src/upstream_oauth2/mod.rs

@@ -139,4 +139,4 @@ fn client_credentials_for_provider(
     };
 
     Ok(client_credentials)
-}
+}