"non-public" revision of jitter in maint/poke-1

[Jose E. Marchesi]

Hi Luca.

Currently make check fails in maint/poke-1 with:

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if test -d ../.git                              \
        && git --version >/dev/null 2>&1; then                  \
  cd .. &&                                              \
  git submodule --quiet foreach                                 \
      'test "$(git rev-parse "$sha1")"                  \
          = "$(git merge-base origin "$sha1")"'         \
    || { echo 'maint.mk: found non-public submodule commit' >&2;        \
         exit 1; };                                             \
else                                                            \
  : ;                                                           \
fi
fatal: run_command returned non-zero status for jitter
.
maint.mk: found non-public submodule commit
../maint.mk:1490: recipe for target 'public-submodule-commit' failed
make: *** [public-submodule-commit] Error 1
------------->>>-----------------------