Better handling of text/uri-list in built-in extensions (#153163)

- When splitting `text/uri-list`, we should split on `\n` to handle against spec versions of `text/uri-list`
- However when constructing a `text/uri-list`, we should use `\r\n` to align with the spec

extensions/markdown-language-features/src/languageFeatures/dropIntoEditor.ts

@@ -44,7 +44,7 @@ export async function tryGetUriListSnippet(document: vscode.TextDocument, dataTr
 	}
 
 	const uris: vscode.Uri[] = [];
-	for (const resource of urlList.split('\r\n')) {
+	for (const resource of urlList.split('\n')) {
 		try {
 			uris.push(vscode.Uri.parse(resource));
 		} catch {