use kramdown's parse_block_html option to ensure the content inside the...

Why is this change being made?

In this commit 7b19a8d8, the resulting render displayed non-processed markdown. This MR now ensures the markdown in the <detail> element gets processed.

Before	After

Does this MR meet the acceptance criteria?

Yes

Assign to DRI

• Did you assign this change to the correct DRI of the page or information you are changing?

Conformity

• Added description to this MR explaining the reasons for the proposed change, per say-why-not-just-what

Closes #6912 (closed)