fb_init_sample: do not clobber yum repos (facebook#308)

Summary:
Pull Request resolved: facebook#308

This should unbreak the CI

Fixes: facebook#307

Differential Revision: D73602355

fbshipit-source-id: 838897339475c3b945182e76e7290fd55c9a7dcd

Author: davide125

cookbooks/fb_init_sample/recipes/default.rb

@@ -30,6 +30,8 @@
 include_recipe 'fb_init_sample::site_settings'
 
 if node.centos?
+  # We turn this off to avoid clobbering /etc/yum,repos.d in the CI
+  node.default['fb_yum_repos']['manage_repos'] = false
   include_recipe 'fb_dnf'
   include_recipe 'fb_rpm'
 end