encoding.xml: fix parsing for self closing empty tags (#19907)

vlib/encoding/xml/parser.v

@@ -562,7 +562,7 @@ pub fn parse_single_node(first_char u8, mut reader io.Reader) !XMLNode {
 	tag_contents := contents.str().trim_space()
 
 	parts := tag_contents.split_any(' \t\n')
-	name := parts[0]
+	name := parts[0].trim_right('/')
 
 	// Check if it is a self-closing tag
 	if tag_contents.ends_with('/') {

vlib/encoding/xml/parser_test.v

@@ -7,6 +7,7 @@ const (
 	<c id="c2">
 		Sample Text
 	</c>
+	<empty/>
 	<c id="c3"/>
 	<abc id="c4"/>
 	<xyz id="c5"/>
@@ -34,6 +35,10 @@ const (
 				'Sample Text',
 			]
 		},
+		XMLNode{
+			name: 'empty'
+			attributes: {}
+		},
 		XMLNode{
 			name: 'c'
 			attributes: {