tests: Add more tests for row_cache::invalidate()
tests: Add more tests for row_cache::invalidate()

Regs #785.

scylladb/scylla,duarten/scylla,duarten/scylla,scylladb/scylla,raphaelsc/scylla,avikivity/scylla,raphaelsc/scylla,raphaelsc/scylla,avikivity/scylla,kjniemi/scylla,kjniemi/scylla,avikivity/scylla,duarten/scylla,scylladb/scylla,scylladb/scylla,kjniemi/scylla