format test failure in __split_ovfl_key_cleanup():
* Eviction cannot free overflow items once a checkpoint is
* running in a tree: that can corrupt the checkpoint's block
* management. Assert that checkpoints aren't running to make
* sure we're catching all paths and to avoid regressions.
S2BT(session)->checkpointing != WT_CKPT_RUNNING ||
In other words, we're evicting a page we can't evict.