CI: Bump Scylla version to 5.1

5.0 is no longer supported.

Author: Lorak-mmk

ci/run_integration_test.sh

@@ -15,7 +15,7 @@ if (( aio_max_nr !=  aio_max_nr_recommended_value  )); then
    fi
 fi
 
-SCYLLA_RELEASE='release:5.0'
+SCYLLA_RELEASE='release:5.1'
 
 python3 -m venv .test-venv
 source .test-venv/bin/activate