ensure dtrt-indent-mode is toggled for config files (conf-mode)

very surprising to me that this is not default dtrt-indent behaviour!

emacs.d/editing.el

@@ -154,7 +154,9 @@
            (hcl-mode        default       (hcl-indent-level tab-width))
            )
          (eval 'dtrt-indent-hook-mapping-list)))
-  (dtrt-indent-global-mode t))
+  (dtrt-indent-global-mode t)
+  ;; NOTE: dtrt-indent-global-mode seems to only hook into 'prog-mode 'text-mode and 'javascript-mode
+  (add-hook 'conf-mode-hook 'dtrt-indent-mode))
 
 (use-package paredit
   :ensure t