emacs-configuration: Remove ob-async

ob-async is depreciated as of org-mode@9.5, as its functionality is now included.

* .guix/rekahsoft/guix-config/home.scm: Remove emacs-ob-async from emacs-manifest
* user-config/emacs/.emacs.d/config.org: Remove ob-async configuration

.guix/rekahsoft/guix-config/home.scm

@@ -177,7 +177,6 @@ single certifcate used for local development with caddy.")
        "emacs-multiple-cursors"
        "emacs-nix-mode"
        "emacs-no-littering"
-       "emacs-ob-async"
        "emacs-org"
        "emacs-org-contrib"
        "emacs-org-download"

user-config/emacs/.emacs.d/config.org

@@ -2013,12 +2013,6 @@ Use [[http://gnuplot.sourceforge.net/][gnuplot]] alongside org-mode to generate
   ;;   :config (org-ac/config-default))
 #+end_src
 
-#+begin_src emacs-lisp
-  (use-package ob-async
-    :after org
-    :config (setq ob-async-no-async-languages-alist '("shell")))
-#+end_src
-
 *** Setup [[https://github.com/IvanMalison/org-projectile][org-projectile]]
 
 #+begin_src emacs-lisp