Investigate flakey `Tests_Admin_wpSiteHealth ::test_object_cache_thresholds()` test

[swissspidy]

The following two tests / datasets sometimes fail for certain hosting providers:

Tests_Admin_wpSiteHealth::test_object_cache_thresholds::test_object_cache_thresholds with data set #2

Tests_Admin_wpSiteHealth::test_object_cache_thresholds with data set #2 ('terms_count', 1)
Failed asserting that false is true.

/tmp/wp-test-runner/tests/phpunit/tests/admin/wpSiteHealth.php:482
Tests_Admin_wpSiteHealth::test_object_cache_thresholds::test_object_cache_thresholds with data set #3

Tests_Admin_wpSiteHealth::test_object_cache_thresholds with data set #3 ('options_count', 100)
Failed asserting that false is true.

/tmp/wp-test-runner/tests/phpunit/tests/admin/wpSiteHealth.php:482

Example: ​https://make.wordpress.org/hosting/test-results/r57871/digitoimistodude-r57871/

Maybe these are just issues with that particular host, but perhaps there's also a opportunity to make the tests more robust. So let's try to look into it to find out more.