Fix .editorconfig (#13735)

These whitespaces introduced in #13698 seem to break my editorconfig
plugin in sublime text resulting in tab-indented files getting converted
to spaces on save.

Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-authored-by: Lauris BH <lauris@nix.lv>

Author: 3 people

.editorconfig

@@ -9,7 +9,7 @@ charset = utf-8
 trim_trailing_whitespace = true
 insert_final_newline = true
 
-[*.{go, tmpl, html}]
+[*.{go,tmpl,html}]
 indent_style = tab
 
 [Makefile]