Merge branch 'ab/ignore-replace-while-working-on-commit-graph'

Teach "git commit-graph" command not to allow using replace objects at all, as we do not use the commit-graph at runtime when we see object replacement. * ab/ignore-replace-while-working-on-commit-graph: commit-graph: don't consider "replace" objects with "verify" commit-graph tests: fix another graph_git_two_modes() helper commit-graph tests: fix error-hiding graph_git_two_modes() helper