Create processor in useEffect in MarkdownHooks

In `MarkdownHooks` we don’t need to create the processor for every
render. We only need it inside the effect.

Author: remcohaszing

lib/index.js

@@ -212,7 +212,6 @@ export async function MarkdownAsync(options) {
  *   React node.
  */
 export function MarkdownHooks(options) {
-  const processor = createProcessor(options)
   const [error, setError] = useState(
     /** @type {Error | undefined} */ (undefined)
   )
@@ -221,6 +220,7 @@ export function MarkdownHooks(options) {
   useEffect(
     function () {
       let cancelled = false
+      const processor = createProcessor(options)
       const file = createFile(options)
 
       processor.run(processor.parse(file), file, function (error, tree) {