Update editor-config.md

Author: MichaelCurrin

recipes/format-and-lint/editor-config.md

@@ -57,6 +57,9 @@ foo = bar
 
 [lib/**.js]
 # ...
+
+[{*.gql,Makefile}]
+# ...
 ```
 
 Some like to put this at the top of the file before `root`.
@@ -211,6 +214,8 @@ indent_style = tab
 indent_size = 4
 ```
 
+See section at the start of this page on mixing `Makefile` with other extensions.
+
 #### GraphQL
 
 ```ini