add in missing backticks for code block

lpmi-13 · lpmi-13 · commit cc82f533c2ba · 2020-02-04T22:33:32.000Z
diff --git a/README.md b/README.md
@@ -653,6 +653,7 @@ Credit: @ccw630
 
 ```vim
 :!$SHELL
+```
 
 ## The AWS CLI Way
 ```
