Fix and restore benchmark step in CI

Benchmark step was failing at least for 2 months - https://github.com/scalacenter/bloop/runs/4675462587?check_suite_focus=true
Because it was also blocking PR which bumps sbt #1679 I decided to remove it temporarily from CI in #1692 until it'll be fixed.

The goal of this issue is to investigate problems, fix them and then add again benchmark to the CI.