Remove unnecessary OAuth code

The parameters provided to the API endpoints only contain the
parameters specified in the method signature so there’s no need to
strip out the OAuth params.

includes/api/class-wc-api-authentication.php

@@ -119,11 +119,6 @@ class WC_API_Authentication {
 		$this->check_oauth_signature( $user, $params );
 		$this->check_oauth_timestamp_and_nonce( $user, $params['oauth_timestamp'], $params['oauth_nonce'] );
 
-		// remove oauth params before further parsing
-		foreach( $param_names as $param_name ) {
-			unset( WC()->api->server->params[ $param_name ] );
-		}
-
 		// authentication successful, return user
 		return $user;
 	}