Merge branch 'mm/rebase-i-post-rewrite-exec' into maint

"git rebase -i" fired post-rewrite hook when it shouldn't (namely, when it was told to stop sequencing with 'exec' insn). * mm/rebase-i-post-rewrite-exec: t5407: use <<- to align the expected output rebase -i: fix post-rewrite hook with failed exec command rebase -i: demonstrate incorrect behavior of post-rewrite