fix: html block test (#927)

[![PR App][icn]][demo] | Fix RM-XYZ
:-------------------:|:----------:

## 🧰 Changes

unskipping and fixing one of the html block tests

## 🧬 QA & Testing

- [Broken on production][prod].
- [Working in this PR app][demo].


[demo]: https://markdown-pr-PR_NUMBER.herokuapp.com
[prod]: https://SUBDOMAIN.readme.io
[icn]:
https://user-images.githubusercontent.com/886627/160426047-1bee9488-305a-4145-bb2b-09d8b757d38a.svg

__tests__/compilers/html-block.test.ts

@@ -13,18 +13,18 @@ describe('html-block compiler', () => {
     expect(mdx(mdast(markdown)).trim()).toBe(markdown.trim());
   });
 
-  it.skip('compiles html blocks with indents', () => {
+  it('compiles html blocks preserving newlines', () => {
     const markdown = `
 <HTMLBlock>{\`
-  <pre><code>
+<pre><code>
 const foo = () => {
   const bar = {
     baz: 'blammo'
   }
 
   return bar
 }
-  </code></pre>
+</code></pre>
 \`}</HTMLBlock>
 `;