checkstyle.xml: comment and whitespace

Author: stephengold

config/checkstyle/checkstyle.xml

@@ -1,8 +1,8 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <!DOCTYPE module PUBLIC
-          "-//Checkstyle//DTD Checkstyle Configuration 1.3//EN"
-          "https://checkstyle.org/dtds/configuration_1_3.dtd">
-<!-- Checkstyle configuration for the j-ogg-all project. -->
+    "-//Checkstyle//DTD Checkstyle Configuration 1.3//EN"
+    "https://checkstyle.org/dtds/configuration_1_3.dtd">
+<!-- Checkstyle configuration for the j-ogg-all project -->
 
 <module name="Checker">
     <property name="charset" value="UTF-8"/>