Merge branch 'pw/rebase-i-error-message' into maint-2.45

When the user adds to "git rebase -i" instruction to "pick" a merge
commit, the error experience is not pleasant.  Such an error is now
caught earlier in the process that parses the todo list.

* pw/rebase-i-error-message:
  rebase -i: improve error message when picking merge
  rebase -i: pass struct replay_opts to parse_insn_line()

diff --cc advice.c
Simple merge

diff --cc sequencer.c
Simple merge

diff --cc sequencer.h
Simple merge