gh-652: make array-api-strict an official dependency

[paddyroddy]

Description

This was missed in #652. This looks like it was because the examples weren't run.

Fixes: #652

Changelog entry

Fixed: Missing array-api-strict dependency

Checks

• Is your code passing linting?
• Is your code passing tests?
• Have you added additional tests (if required)?
• Have you modified/extended the documentation (if required)?
• Have you added a one-liner changelog entry above (if required)?

[paddyroddy]

Label not working as expected, have raised #654

[paddyroddy]

Bit confused as from #655 it appears that main was indeed working. However, #642 appears to need this, so makes sense to merge.