Parametrize mcp_docker_registry host

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

Change-Id: I36ad55a1960f6c8e025d9c967bbc7658927fc872
diff --git a/jenkins/client/job/validate.yml b/jenkins/client/job/validate.yml
index 112cb3d..57db539 100644
--- a/jenkins/client/job/validate.yml
+++ b/jenkins/client/job/validate.yml
@@ -2,6 +2,7 @@
   _param:
     jenkins_salt_api_url: "http://${_param:salt_master_host}:6969"
     cvp_sanity_default_repo: "https://github.com/Mirantis/cvp-sanity-checks"
+    mcp_docker_registry: 'docker-prod-local.artifactory.mirantis.com'
   jenkins:
     client:
       view:
@@ -37,7 +38,7 @@
               description: Credentials to the Salt API
             TEST_IMAGE:
               type: string
-              default: "docker-prod-local.artifactory.mirantis.com/mirantis/oss/qa-tools"
+              default: "${_param:mcp_docker_registry}/mirantis/oss/qa-tools"
               description: Docker image to setup testing environment
             TARGET_NODE:
               type: string