As described in SERVER-40167, seeking using search_near can cause operations to encounter unintended prepare conflicts when the queried key is not found.
Enforce prepare conflicts on secondaries
Abort transactions that perform updates with ignore_prepare=true
Index key removal should not encounter prepare conflicts on unrelated keys
Add failpoint to skip doing retries on WiredTiger prepare conflicts
Test cases in txn_commit_optimizations_for_read_only_shards.js are not isolated from each other