Code blocks not fully ignored when in `style` tag

Hi,
I'm using juice to pack an HTML file which uses Handlebars, and I found what seems to be a bug. Here's the [reproduction](https://runkit.com/embed/jzmmmgmx0tf0).

To sum it up, if we process the following HTML:
```

.somediv {
color: blue;
}

You can see that the second example is missing its closing `{{/if}}`
I tried playing around and adding several, more specific, options to `codeBlocks`, but to no avail.

Start with the linked RunKit reproduction and inspect how Juice processes style-tag contents and the codeBlocks option. Compare both Handlebars examples; done means the second example retains its closing {{/if}} after CSS inlining.

Written by the indexing model from the issue text.