[infrared] install git before using it

Some tester nodes may not have git installed
The tobiko infrared plugin should check git is installed before using it
to checkout the specified tobiko version

Change-Id: Icac436fe4070c3b902905271379a2a00f7e1d6ea

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

@@ -16,6 +16,13 @@
         state: directory
       register: create_dest_dir
 
+    - name: install git
+      ignore_errors: yes
+      become: true
+      package:
+        name: git
+        state: present
+
     - name: "checkout files from '{{ deploy_git_repo }}[{{ deploy_git_refspec }}]' to '{{ deploy_dir }}'"
       git:
         dest: '{{ deploy_dir }}'