chore: fix serialize_data comment typo (#15518)

Related issue: none. This is a small comment-only fix.

- Removes a duplicated `until` in
`packages/kit/src/runtime/server/page/serialize_data.js`.

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---------

Co-authored-by: rohan436 <rohan.santhoshkumar@googlemail.com>
Co-authored-by: Tee Ming <chewteeming01@gmail.com>

Author: 3 people

packages/kit/src/runtime/server/page/serialize_data.js

@@ -6,7 +6,7 @@ import { hash } from '../../../utils/hash.js';
  *
  * The first closes the script element, so everything after is treated as raw HTML.
  * The second disables further parsing until `-->`, so the script element might be unexpectedly
- * kept open until until an unrelated HTML comment in the page.
+ * kept open up until an unrelated HTML comment in the page.
  *
  * U+2028 LINE SEPARATOR and U+2029 PARAGRAPH SEPARATOR are escaped for the sake of pre-2018
  * browsers.