WP_User::remove_cap( string $cap )

	public function remove_cap( $cap ) {
		if ( ! isset( $this->caps[ $cap ] ) ) {
			return;
		}
		unset( $this->caps[ $cap ] );
		update_user_meta( $this->ID, $this->cap_key, $this->caps );
		$this->get_role_caps();
		$this->update_user_level_from_caps();
	}