Scan plugins by default, but don’t scan node_modules or vendor as the…

…y’re not our code

phpcs.xml

@@ -7,8 +7,9 @@
 	<file>./mu-plugins/*</file>
 
 	<!-- Don't scan these directories -->
+	<exclude-pattern>node_modules/</exclude-pattern>
+	<exclude-pattern>vendor/</exclude-pattern>
 	<exclude-pattern>dist/</exclude-pattern>
-	<exclude-pattern>./plugins/*</exclude-pattern>
 
 	<rule ref="10up-Default" />