Retracted: Retract v1.11.0 through v1.11.2 because they contain a data race bug in
operation memory pooling that may cause undefined behavior when reading
raw BSON responses in error documents. Resolved by GODRIVER-2677.
NewLockedRand returns a new "x/exp/rand" pseudo-random number generator seeded with a
cryptographically-secure random number.
It is safe to use from multiple goroutines.