Add long running replication tests

These tests will help verify that replication, both physical and
logical, works as expected in Neon.

Co-authored-by: Sasha Krassovsky <sasha@neon.tech>

.github/actions/run-python-test-set/action.yml

@@ -115,6 +115,7 @@ runs:
         export POSTGRES_DISTRIB_DIR=${POSTGRES_DISTRIB_DIR:-/tmp/neon/pg_install}
         export DEFAULT_PG_VERSION=${PG_VERSION#v}
         export LD_LIBRARY_PATH=${POSTGRES_DISTRIB_DIR}/v${DEFAULT_PG_VERSION}/lib
+        export BENCHMARK_CONNSTR=${BENCHMARK_CONNSTR:-}
 
         if [ "${BUILD_TYPE}" = "remote" ]; then
           export REMOTE_ENV=1