test-build-validate-cleanup job is broken

This hello's job should fail: https://salsa.debian.org/santiago/hello/-/jobs/8314345, with this error:

I: Finished running 'cd /build/package//package && ./debian/rules clean'.

bash -c 'find /build/package//package -print0 |
                  sort -z |
                  while read -d $'\''\0'\'' file; do
                      echo -n "$(stat -c "%n %F %s" "${file}") "
                      if [ -f "${file}" ]; then
                          sha256sum "${file}" |
                              cut -d " " -f 1
                      else
                              echo
                      fi
                  done > /tmp/file-list.post-build'
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------


I: Finished running 'bash -c 'find /build/package//package -print0 |
                  sort -z |
                  while read -d $'\''\0'\'' file; do
                      echo -n "$(stat -c "%n %F %s" "${file}") "
                      if [ -f "${file}" ]; then
                          sha256sum "${file}" |
                              cut -d " " -f 1
                      else
                              echo
                      fi
                  done > /tmp/file-list.post-build''.

diff /tmp/file-list.pre-build /tmp/file-list.post-build
-------------------------------------------------------

15d14
< /build/package//package/INSTALL regular file 15752 e07808836b9bd90b07bc32117cde46b06821ff718514f575719a0ec5c306a24a
17d15
< /build/package//package/Makefile.in regular file 143282 fd2e61ceb1eaf69178108807e8130b89e37df8f0fe20d9c7cf5b7e34d4d4426e
24d21
< /build/package//package/aclocal.m4 regular file 43830 4c375e6bb43706cd1aa2d517e529cf022e806957a07301194c56196dfd923f6a
27d23
< /build/package//package/build-aux/compile regular file 7333 c8af04e62bad4ab75dafd22119026e5e3943f385bdcbe7731a4938102453754c
29d24
< /build/package//package/build-aux/config.rpath regular file 18574 9fcac06e44bb214ec5ea21f950235c858de370c60b7b3e85b73f65edf51135aa
31d25
< /build/package//package/build-aux/depcomp regular file 22464 e392b6508e6af95d02a04b117cc0cd5bc9543af68be4e73a3d898b3c2713215d
37,39d30
< /build/package//package/build-aux/install-sh regular file 14675 d7c113e5484fce8b48f9a34a7a91e385ec279247d415b0b7d749bd56ad8ee8a2
< /build/package//package/build-aux/mdate-sh regular file 6047 2a25d2151e2bf3c4668011b6cf6002419d596b3de261c29b03d0c8d8a54d028a
< /build/package//package/build-aux/missing regular file 6872 f038345dab184e538098d22a8edc423762da66a90ebe269f23bfef85287cd30c
46,47d36
< /build/package//package/build-aux/test-driver regular file 4287 7a61b6f471355eeab543191d9eb1e3efbb81709f0e3389c811721f43a9c68938
< /build/package//package/build-aux/texinfo.tex regular file 326981 298be0b84dad4c98240e023ec99d91dc0fd169be33171e206723ab072aed872c
51,52d39
...
E: Command 'diff /tmp/file-list.pre-build /tmp/file-list.post-build' failed to run.

Thanks to @otto for spotting this.