Avoid update hook during git-rebase --interactive

If we are rebasing changes that contain potential whitespace
errors that our .git/hooks/pre-commit hook looks for and fails
on then git-commit will fail to commit that change.  This causes
git-rebase--interactive to squash commits together, even though it
was not requested to do so by the todo file.

Passing --no-verify to git-commit makes git-rebase -i behave more
like git-rebase normally would in such conditions, providing more
consistent behavior between the different rebase implementations.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

git-rebase--interactive.sh

@@ -296,7 +296,7 @@ do_next () {
 			GIT_AUTHOR_NAME="$GIT_AUTHOR_NAME" \
 			GIT_AUTHOR_EMAIL="$GIT_AUTHOR_EMAIL" \
 			GIT_AUTHOR_DATE="$GIT_AUTHOR_DATE" \
-			$USE_OUTPUT git commit -F "$MSG" $EDIT_COMMIT
+			$USE_OUTPUT git commit --no-verify -F "$MSG" $EDIT_COMMIT
 			;;
 		t)
 			cp "$MSG" "$GIT_DIR"/MERGE_MSG
@@ -372,7 +372,7 @@ do
 			test ! -f "$DOTEST"/amend || git reset --soft HEAD^
 		} &&
 		export GIT_AUTHOR_NAME GIT_AUTHOR_EMAIL GIT_AUTHOR_DATE &&
-		git commit -F "$DOTEST"/message -e
+		git commit --no-verify -F "$DOTEST"/message -e
 
 		require_clean_work_tree
 		do_rest