[scripts][before_tests] Fix python 2 print syntax

scripts/before_test.sh

@@ -91,7 +91,7 @@ check_array_env ALGORITHMS
 if [ "${BUILDOUT}" == "true" ]; then
   BEAT_CORE_TEST_DIR="${basedir}/beat/core/test"
 else
-  BEAT_CORE_TEST_DIR=$(python -c 'import beat.core.test as f; import os; print os.path.abspath(os.path.dirname(f.__file__))')
+  BEAT_CORE_TEST_DIR=$(python -c 'import beat.core.test as f; import os; print(os.path.abspath(os.path.dirname(f.__file__)))')
 fi
 check_env BEAT_CORE_TEST_DIR