fail if is integer/float

Author: Marco Gorelli

pandas/_libs/tslib.pyx

@@ -655,16 +655,6 @@ cpdef array_to_datetime(
                         _ts = convert_datetime_to_tsobject(py_dt, None)
                         iresult[i] = _ts.value
                     if not string_to_dts_failed:
-                        if require_iso8601:
-                            if is_coerce:
-                                iresult[i] = NPY_NAT
-                                continue
-                            elif is_raise:
-                                raise ValueError(
-                                    f"time data \"{val}\" at position {i} doesn't "
-                                    f"match format \"{format}\""
-                                )
-                            return values, tz_out
                         # No error reported by string_to_dts, pick back up
                         # where we left off
                         value = npy_datetimestruct_to_datetime(NPY_FR_ns, &dts)