Make sure we use correct resource when accessing the `[markdown]` config setting

Fixes #51650

extensions/markdown-language-features/src/features/previewConfig.ts

@@ -27,7 +27,7 @@ export class MarkdownPreviewConfiguration {
 	private constructor(resource: vscode.Uri) {
 		const editorConfig = vscode.workspace.getConfiguration('editor', resource);
 		const markdownConfig = vscode.workspace.getConfiguration('markdown', resource);
-		const markdownEditorConfig = vscode.workspace.getConfiguration('[markdown]');
+		const markdownEditorConfig = vscode.workspace.getConfiguration('[markdown]', resource);
 
 		this.scrollBeyondLastLine = editorConfig.get<boolean>('scrollBeyondLastLine', false);