fix(creator-studio): unify block and inline marker deletion

assets/creator-studio/src/utils/block-markup.ts

@@ -88,7 +88,7 @@ export function mathMarkup({ formula, display }: MathOptions): string {
 	const attrs = `data-jio-math-source="${escapeHtml(formula.trim())}" data-jio-math-display="${display ? '1' : '0'}"`;
 	return display
 		? `<p><span class="jio-math jio-math--block" ${attrs} contenteditable="false">${body}</span></p>`
-		: `<span class="jio-math" ${attrs}>${body}</span>`;
+		: `<span class="jio-math" ${attrs} contenteditable="false">${body}</span>`;
 }
 
 /**