STY: Use 4-space indentation for TOML

Author: ghisvail

.editorconfig

@@ -13,6 +13,11 @@ insert_final_newline = true
 indent_size = 4
 indent_style = space
 
+# Use 4-space indentation for TOML.
+[*.toml]
+indent_size = 4
+indent_style = space
+
 # Use 2-space indentation for YAML.
 [*.{yml,yaml}]
 indent_size = 2