Testing for MDEV-36055: Optimise reorderable LEFT JOINs

MDEV-36055 has a basic patch:

28ad2c33ff9 upstream/bb-12.2-mdev-36055-no-dep-merge MDEV-36055 [check-ci] Do not merge inner table dep with outer nested_join ones

We know the patch causes slowdowns with @@optimizer_prune_level=1 (or higher) due to pruned_by_heuristic pruning.

We need test it with @@optimizer_prune_level=0. Two kinds of testing are needed:

• A. Correctness
• B. Slowdowns

The test queries should be a mix of INNER and OUTER joins.
Do not run joins of more than 10 tables (as that may work slowly with optimizer_prune_level=0).

The version to run against is the commit right before the mentioned one:
git log --oneline 28ad2c33ff9

28ad2c33ff9 (origin/bb-12.2-mdev-36055-no-dep-merge) MDEV-36055 [check-ci] Do not merge inner table dep with outer nested_join ones

46d7450f752 MDEV-35635: START SLAVE UNTIL allows CHANGE MASTER TO options

46d7450f752