Parametrize mcp_docker_registry host

Related-Bug: PROD-22480 (PROD:22480)

Change-Id: I36ad55a1960f6c8e025d9c967bbc7658927fc872
diff --git a/jenkins/client/job/test_pipelines.yml b/jenkins/client/job/test_pipelines.yml
index d18b281..c8eaab0 100644
--- a/jenkins/client/job/test_pipelines.yml
+++ b/jenkins/client/job/test_pipelines.yml
@@ -1,4 +1,6 @@
 parameters:
+  _param:
+    mcp_docker_registry: 'docker-dev-local.docker.mirantis.net'
   jenkins:
     client:
       job_template:
@@ -48,7 +50,7 @@
                 default: "gerrit"
               GRADLE_IMAGE:
                 type: string
-                default: "docker-dev-local.docker.mirantis.net/mirantis/cicd/niaquinto_gradle"
+                default: "${_param:mcp_docker_registry}/mirantis/cicd/niaquinto_gradle"
               GRADLE_CMD:
                 type: string
                 default: "check --info"