tobiko IR version : set default execution version to 0.3.1 tag

Change-Id: If98f681b7039e36f26059417b6645d2193a7bfb8

infrared_plugin/roles/tobiko-ir-init/tasks/main.yaml

@@ -12,7 +12,7 @@
   vars:
     deploy_dir: '{{ tobiko_src_dir | realpath }}'
     deploy_git_repo: '{{ tobiko_git_repo }}'
-    deploy_git_refspec: "{{ tobiko_git_refspec | default('latest') }}"
+    deploy_git_refspec: "{{ tobiko_git_refspec | default('0.3.1') }}"
     deploy_git_remote: "{{ tobiko_git_remote | default('') }}"
   when: create_tobiko_dir is changed