refactor(salt-lint): fix violations

```
[213] SaltStack recommends using cmd.run together with onchanges, rather than cmd.wait
apt/dist_upgrade.sls:2
  cmd.wait:
[213] SaltStack recommends using cmd.run together with onchanges, rather than cmd.wait
apt/update.sls:2
  cmd.wait:
[213] SaltStack recommends using cmd.run together with onchanges, rather than cmd.wait
apt/upgrade.sls:2
  cmd.wait:
[214] SLS file with a period in the name (besides the suffix period) can not be referenced
test/salt/pillar/preferences.pillar.sls:1
[214] SLS file with a period in the name (besides the suffix period) can not be referenced
test/salt/pillar/repositories.pillar.sls:1
[214] SLS file with a period in the name (besides the suffix period) can not be referenced
test/salt/pillar/unattended.pillar.sls:1
```

apt/dist_upgrade.sls

 apt-get -y dist-upgrade:
-  cmd.wait:
-    - watch:
+  cmd.run:
+    - onchanges:
       - file: /etc/apt/sources.list
       - file: /etc/apt/sources.list.d

apt/update.sls

 apt-get -y update:
-  cmd.wait:
-    - watch:
+  cmd.run:
+    - onchanges:
       - file: /etc/apt/sources.list
       - file: /etc/apt/sources.list.d

apt/upgrade.sls

 apt-get -y upgrade:
-  cmd.wait:
-    - watch:
+  cmd.run:
+    - onchanges:
       - file: /etc/apt/sources.list
       - file: /etc/apt/sources.list.d

kitchen.yml

             '*':
               - apt
       pillars_from_files:
-        apt.sls: test/salt/pillar/repositories.pillar.sls
+        apt.sls: test/salt/pillar/repositories.sls
     verifier:
       inspec_tests:
         - path: test/integration/repositories
             '*':
               - apt
       pillars_from_files:
-        apt.sls: test/salt/pillar/preferences.pillar.sls
+        apt.sls: test/salt/pillar/preferences.sls
     verifier:
       inspec_tests:
         - path: test/integration/preferences
             '*':
               - apt
       pillars_from_files:
-        apt.sls: test/salt/pillar/unattended.pillar.sls
+        apt.sls: test/salt/pillar/unattended.sls
     verifier:
       inspec_tests:
         - path: test/integration/unattended