lang/org: use correct todo keyword on M-RET
lang/org: use correct todo keyword on M-RET

Previously, new TODO headers created with M-RET or M-S-RET (bound to
+org/insert-item) would use the first TODO keyword in org-todo-keywords
in the new header. This wouldn't necessarily match the previous header.
e.g.

* [ ] Item 1
* TODO |

This fix ensures new headers will preserve the correct header, even if
the previous one is in a DONE state.

* [ ] Item 1
* [ ] |

hlissner/.emacs.d,UndeadKernel/emacs_doom,hlissner/doom-emacs,hlissner/doom-emacs,hlissner/.emacs.d,UndeadKernel/emacs_doom,hlissner/.emacs.d,UndeadKernel/emacs_doom,hlissner/doom-emacs,UndeadKernel/emacs_doom,UndeadKernel/emacs_doom,hlissner/.emacs.d,UndeadKernel/emacs_doom,hlissner/.emacs.d,hlissner/doom-emacs,hlissner/doom-emacs,UndeadKernel/emacs_doom,hlissner/.emacs.d,hlissner/.emacs.d,hlissner/doom-emacs,hlissner/doom-emacs,hlissner/.emacs.d