gnulib-tool: Ignore autom4te.cache when using GNULIB_TOOL_IMPL=sh+py. Reported by Paul Eggert in: <https://lists.gnu.org/archive/html/bug-gnulib/2024-05/msg00061.html>. * gnulib-tool: Don't compare the autom4te.cache directory since requests are not sorted in Autoconf version 2.71 and below.