Updated common bench to use COMMON_BENCH_VERSION

.gitlab-ci.yml

@@ -37,7 +37,11 @@ stages:
 common:setup:
   stage: config
   before_script:
-    - git clone https://eicweb.phy.anl.gov/EIC/benchmarks/common_bench.git setup 
+    - |
+      if [[ -z "${COMMON_BENCH_VERSION}" ]] ; then
+        export COMMON_BENCH_VERSION="master" 
+      fi
+      git clone -b "${COMMON_BENCH_VERSION}" https://eicweb.phy.anl.gov/EIC/benchmarks/common_bench.git setup 
   script:
     - |
       if [[ "x${CI_PIPELINE_SOURCE}" == "xmerge_request_event"  || "$CI_COMMIT_BRANCH" == "master" ]]; then