This fix is a backport of Bug#24464763.

This is a test script fix only, to improve test robustness.
Before this fix, some tests failed with spurious diff
related to 'Performance_schema_table_instances_lost in the
result file. This is due to the MTR suite default
configuration, default_mysqld.cnf, which uses a fixed number
of instrumented objects: for some combinations of tests, the
number of items actually instrumented during the test
payload can exceed artificial limits set in the test cnf.
The fix is to relax limits on the number of instrumented
objects, and rely on performance schema buffers scaling
automatically based on the load.

Adjusted the test results accordingly.

RB: 25566