[xml] MissingEncoding - fix rule metadata

pmd-xml/src/main/resources/category/xml/bestpractices.xml

@@ -10,18 +10,20 @@ Rules which enforce generally accepted best practices.
     </description>
     
     <rule name="MissingEncoding"
-      language="xml"
-      message="Set an explicit XML encoding in the XML declaration to ensure proper parsing"
-      class="net.sourceforge.pmd.lang.rule.XPathRule">
+          language="xml"
+          since="7.0.0"
+          message="Set an explicit XML encoding in the XML declaration to ensure proper parsing"
+          class="net.sourceforge.pmd.lang.rule.XPathRule"
+          externalInfoUrl="${pmd.website.baseurl}/pmd_rules_xml_bestpractices.html#missingencoding">
        <description>
-          When the character encoding is missing from the XML declaration,
-          the parser may produce garbled text.
-    
-          This is completely dependent on how the parser is set up
-          and the content of the XML file, so it may be hard to reproduce.
-    
-          Providing an explicit encoding ensures  accurate and consistent
-          parsing.
+When the character encoding is missing from the XML declaration,
+the parser may produce garbled text.
+
+This is completely dependent on how the parser is set up
+and the content of the XML file, so it may be hard to reproduce.
+
+Providing an explicit encoding ensures  accurate and consistent
+parsing.
        </description>
        <priority>3</priority>
        <properties>

pmd-xml/src/main/resources/category/xml/categories.properties

@@ -3,12 +3,12 @@
 #
 
 rulesets.filenames=\
+    category/xml/bestpractices.xml,\
     category/xml/errorprone.xml
 
 #
 # categories without rules
 #
-# category/xml/bestpractices.xml
 # category/xml/codestyle.xml
 # category/xml/design.xml
 # category/xml/documentation.xml