S3 api DeleteObject fix invalid XML (#1324)

linked to #1323

Do only check element nodes when validating XML content (skip text
nodes).

If text nodes are skipped then the validation fails when providing
formatted XML content as body of the request.

Co-authored-by: frederic vroman <fred@lesmouths.net>
Reviewed-on: https://git.deuxfleurs.fr/Deuxfleurs/garage/pulls/1324
Co-authored-by: bytechunk <bytechunk.a52b055@track-it.pw>
Co-committed-by: bytechunk <bytechunk.a52b055@track-it.pw>

src/api/s3/delete.rs

@@ -132,6 +132,14 @@ fn parse_delete_objects_xml(xml: &roxmltree::Document) -> Option<DeleteRequest>
 	}
 
 	for item in delete.children() {
+		// Only parse <Part> nodes
+		if !item.is_element() {
+			// text nodes are allowed only if they contain whitespace characters only
+			if !item.text()?.trim().is_empty() {
+				return None;
+			}
+		}
+
 		if item.has_tag_name("Object") {
 			let key = item.children().find(|e| e.has_tag_name("Key"))?;
 			let key_str = key.text()?;