Fix bug where ruby keywords in comments would be highlighted.

Not sure how this is the fix. The documentation basically said I was
doing the right thing and this seems to be the exact opposite.

Cribbed off of ruby-mode for this fix. 🤷

enh-ruby-mode.el

@@ -460,7 +460,7 @@ Warning: does not play well with command ‘electric-indent-mode’."
               'enh-ruby-add-log-current-method)
 
   (setq-local font-lock-keywords    enh-ruby-font-lock-keywords)
-  (setq font-lock-defaults          '((enh-ruby-font-lock-keywords) t))
+  (setq font-lock-defaults          '((enh-ruby-font-lock-keywords) nil))
   (setq indent-tabs-mode            enh-ruby-indent-tabs-mode)
   (setq imenu-create-index-function 'enh-ruby-imenu-create-index)