Change tab width go,tmpl,html to 2 (#12572)

Make it easier to edit deeply nested code. I plan to convert Less to
2-space so that we have standardized indentation width in the codebase.

Co-authored-by: techknowlogick <techknowlogick@gitea.io>

.editorconfig

@@ -11,7 +11,7 @@ trim_trailing_whitespace = false
 
 [*.{go,tmpl,html}]
 indent_style = tab
-indent_size = 4
+indent_size = 2
 
 [*.{less,css}]
 indent_style = space