[9.18] fix: test: Fix flaky reclimit test

The max-types-per-name cache eviction tests were flaky because two test steps were missing a sleep between queries, causing TTL-based cache verification to fail when both queries completed within the same second.

Backport of MR !11782

Merge branch 'backport-ondrej/fix-flaky-reclimit-9.18' into 'bind-9.18'

See merge request isc-projects/bind9!12028