Block theme: Archive, Category and Search pages don't have an `h1` tag.

[StevenDufresne]

Describe the bug

Unlike the showcase archives which include an h1, this block theme does not include any on the following pages:

• https://wordpress.org/patterns/?s=test&pattern-categories=query
• https://wordpress.org/patterns/categories/query/
• https://wordpress.org/patterns/archives/

Showcase

<h1 class="screen-reader-text wp-block-query-title">All sites</h1>