sort repos so they do not change order every run

linux/files/sources.list

@@ -1,4 +1,4 @@
-{%- for name, repo in default_repos.items() %}
+{%- for name, repo in default_repos.items() | sort %}
 # Repository {{ name }}
 {{ repo.source }}
 {%- endfor %}

linux/system/repo.sls

@@ -36,7 +36,7 @@ purge_sources_list_d_repos:
   - clean: True
   {%- endif %}
 
-  {%- for name, repo in system.repo.items() %}
+  {%- for name, repo in system.repo.items() | sort %}
     {%- set name=repo.get('name', name) %}
     {%- if grains.os_family == 'Debian' %}