CORD-984 Retry adding PPAs

Change-Id: I148de86eb848081043d8e81f27b8bd5c7fef24f7
diff --git a/ansible/roles/buildtools/tasks/main.yml b/ansible/roles/buildtools/tasks/main.yml
index 3ade330..600b664 100644
--- a/ansible/roles/buildtools/tasks/main.yml
+++ b/ansible/roles/buildtools/tasks/main.yml
@@ -3,6 +3,10 @@
     repo: ppa:git-core/ppa
     state: present
     update_cache: yes
+  register: result
+  until: result | success
+  retries: 3
+  delay: 10
 
 - name: Apt packages
   apt: