Disable M-035 for white-label productions

Such productions may contain a colophon, but don't necessarily use the
same identifier format as Standard Ebooks.

Arguably all of these special-file checks could be disabled for
white-label productions, but this one stands out as not applying.

se/se_epub_lint.py

@@ -1349,7 +1349,7 @@ def _lint_special_file_checks(self, filename: Path, dom: se.easy_xml.EasyXmlTree
 			messages.append(LintMessage("s-016", "Incorrect [text]the[/] before Google Books link.", se.MESSAGE_TYPE_ERROR, filename, ["the<br/>\n" + node.to_string() for node in nodes]))
 
 		se_url = self.generated_identifier.replace("url:", "")
-		if not dom.xpath(f"/html/body//a[@href='{se_url}' and text()='{se_url.replace('https://', '')}']"):
+		if self.is_se_ebook and not dom.xpath(f"/html/body//a[@href='{se_url}' and text()='{se_url.replace('https://', '')}']"):
 			messages.append(LintMessage("m-035", f"Unexpected S.E. identifier in colophon. Expected: [url]{se_url}[/].", se.MESSAGE_TYPE_ERROR, filename))
 
 		if self.metadata_dom.xpath("/package/metadata/meta[@property='role' and text()='trl']") and "translated from" not in file_contents: