remove benchmark hook (#5149)
remove benchmark hook (#5149)

Remove an ad hoc leftover hook for benchmarking inserts.
lolski/grakn,lolski/grakn,graknlabs/grakn,lolski/grakn,lolski/grakn,graknlabs/grakn,graknlabs/grakn,graknlabs/grakn