Run "make update-copyright" and then...
* tests/sample-test: Adjust to use the single most recent year.
* tests/du/bind-mount-dir-cycle-v2.sh: Fix case in copyright message,
so that year is updated automatically in future.
Run "make update-copyright", but then also run this,
perl -pi -e 's/2\d\d\d-//' tests/sample-test
to make that one script use the single most recent year number.
* src/timeout.c (unblock_signal): A new function to unblock a
specified signal, or warn if not possible.
(set_timeout): Ensure SIGALRM is unblocked before we setup the timer.
* tests/misc/timeout-blocked.pl: A new test for the issue.
* tests/local.mk: Reference the new test.
* NEWS: Mention the fix.
Fixes: http://bugs.gnu.org/13535
