Attached is a patch to restore the window configuration after exiting an
org source buffer, when org-src-window-setup is one of reorganize-frame,
split-window-below, or split-window-right.

References:
https://lists.gnu.org/archive/html/emacs-orgmode/2019-12/msg00263.html
https://lists.gnu.org/archive/html/emacs-orgmode/2018-11/msg00253.html