.gitlab-ci.yml: benchmark with docker

.gitlab-ci.yml

@@ -371,6 +371,10 @@ ff45-server-functional:
 # Benchmark
 
 benchmark_algo:
+  image:  gcc:6.3
+  before_script:
+    - apt-get update
+    - apt-get install -y time valgrind python3 wget tar
   stage: benchmark
   script:
     - cd algo/tests ; python3 benchmark-releases.py -bic
@@ -378,7 +382,7 @@ benchmark_algo:
   only:
     - /^feature-.*a.*\/.*$/
   tags:
-    - several-compilers
+    - cidocker
 
 
 # Deployment