Full block import benchmark (#4865)

* full block import benchmark

* try rocksdb cache

* add profiling helper

* use random keyring instead of zero caching

* update docs

* add more io stats

* remove last sentence

* add ci job to see

* Update primitives/keyring/src/sr25519.rs

Co-Authored-By: Marcio Diaz <[email protected]>

* switch to 100tx-block

* remove ci script

Co-authored-by: Marcio Diaz <[email protected]>