Adding yamllinter to ci steps (#1556)

* Adding yaml linter to ci check

* Minor linting fixes from yamllint

* Changing CI to install python pkgs from requirements.txt

- adding in a secondary requirements.txt for tests
- moving yamllint to tests requirements

roles/dnsmasq/templates/dnsmasq-deploy.yml

@@ -35,7 +35,6 @@ spec:
             capabilities:
               add:
                 - NET_ADMIN
-          imagePullPolicy: IfNotPresent
           resources:
             limits:
               cpu: {{ dns_cpu_limit }}
@@ -64,4 +63,3 @@ spec:
           hostPath:
             path: /etc/dnsmasq.d-available
       dnsPolicy: Default  # Don't use cluster DNS.
-