fix the shift+enter

zsh/merge-main.sh

@@ -1,6 +1,6 @@
 #!/usr/bin/bash -e
 branch=$(git status|head -1|cut -f3 -d\ )
-git checkout main
+git checkout $(git_main_branch)
 git pull
 git checkout "$branch"
-git merge main
+git merge $(git_main_branch)