Update .editorconfig (#3534)

[CI SKIP]

.editorconfig

@@ -5,8 +5,17 @@ root = true
 [*]
 charset = utf-8
 end_of_line = lf
+insert_final_newline = true
+trim_trailing_whitespace = true
+
+[*.{go,tmpl}]
 indent_style = tab
+indent_size = 4
 
-[*.yml]
+[*.{less,yml}]
 indent_style = space
 indent_size = 2
+
+[*.js]
+indent_style = space
+indent_size = 4