Merge branch 'ps/test-set-e-clean' into next

The test suite harness and many individual test scripts have been
updated to work correctly when 'set -e' is in effect, which helps
detect misspelled test commands.

* ps/test-set-e-clean:
  t: detect errors outside of test cases
  t9902: fix use of `read` with `set -e`
  t6002: fix use of `expr` with `set -e`
  t1301: don't fail in case setfacl(1) doesn't exist or fails
  t0008: silence error in subshell when using `grep -v`
  t: prepare `test_when_finished ()`/`test_atexit()` for `set -e`
  t: prepare execution of potentially failing commands for `set -e`
  t: prepare conditional test execution for `set -e`
  t: prepare `git config --unset` calls for `set -e`
  t: prepare `stop_git_daemon ()` for `set -e`
  t: prepare `test_must_fail ()` for `set -e`
  t: prepare `test_match_signal ()` calls for `set -e`

diff --cc ci/run-build-and-tests.sh
index e2d783d90b0181697b10352c0357a565daf5afe5,de08a08d59fc8f598ebe0f666a0454b7085e88fe..1d9a0a736d255be2e7c64c910952623737de4c64
--- 1/ci/run-build-and-tests.sh
--- 2/ci/run-build-and-tests.sh
+++ b/ci/run-build-and-tests.sh
@@@ -8,12 -8,17 +8,19 @@@
  export TEST_CONTRIB_TOO=yes
  
  case "$jobname" in
 +linux-musl-meson)
 +      MESONFLAGS="$MESONFLAGS -Drust=disabled"
++      export GIT_TEST_USE_SET_E=yes
 +      ;;
+ almalinux-*|debian-*|fedora-*|linux-*)
+       export GIT_TEST_USE_SET_E=yes
+       ;;
+ esac
+ 
+ case "$jobname" in
  fedora-breaking-changes-musl|linux-breaking-changes)
        export WITH_BREAKING_CHANGES=YesPlease
 -      export WITH_RUST=YesPlease
        MESONFLAGS="$MESONFLAGS -Dbreaking_changes=true"
 -      MESONFLAGS="$MESONFLAGS -Drust=enabled"
        ;;
  linux-TEST-vars)
        export OPENSSL_SHA1_UNSAFE=YesPlease