rule WordPress-Extra exclude Generic.Strings.UnnecessaryStringConcat

allows human readable multiple font enqueue

wp_enqueue_style( static::$slug . "-fonts", "//fonts.googleapis.com/css?family="
    . "Droid+Serif:400,700,400italic,700italic|"
    . "Roboto:400,900,400italic,900italic|"
    . "Source+Sans+Pro:400,600,700,900,400italic,600italic,900italic"
);

Conversion-Ready/ruleset.xml

@@ -20,6 +20,7 @@
 	</rule>
 
 	<rule ref="WordPress-Extra">
+		<exclude name="Generic.Strings.UnnecessaryStringConcat" />
 	</rule>
 
 	<rule ref="WordPress-VIP">