[CI] Make the bench use the ENABLE_JUNIT_REPORT option and use it on CI

Summary:
This adds the required arguments at build system level to generate the
junit report from the benchmark, and simplify the CI script by using
this feature.

Depends on D7064.

Test Plan:

ninja bitcoin-bench

Check the bench runs as usual, and prints human readable result.

cmake -GNinja -DENABLE_JUNIT_REPORT=ON
ninja bitcoin-bench

Check the bench reports to a junit file in test/junit

./contrib/teamcity/build-configurations.py build-bench

Reviewers: #bitcoin_abc, deadalnix

Reviewed By: #bitcoin_abc, deadalnix

Subscribers: deadalnix

Differential Revision: https://reviews.bitcoinabc.org/D7070