Previously, ltrimstr/rtrimstr would just let the input pass through for non-string inputs or arguments. That was happening because, they were leaking the errors returned by startswith/endswith treating them as if they were jv_false(). The leak was resolved by #2977 for 1.7.1 This patch rewrites ltrimstr and rtrimstr in jq, and makes them not ignore startswith and endswith errors anymore.