Description of problem:
Ansible-playbook duplicates the nodeSelector on the daemonset for template service broker making the pods fail to start. The installer adds the label 'node-role.kubernetes.io/master=true' to the daemonset of the apiserver pods, so when using the variable to set a nodeSelector, e.g. template_service_broker_selector={"node-role.kubernetes.io/infra": "true"}, the daemonset will end up with both labels on the nodeSelector making the pods to not start.

Version-Release number of the following components:
openshift-ansible-roles-3.11.92-1.git.0.f2fade7.el7.noarch
openshift-ansible-playbooks-3.11.92-1.git.0.f2fade7.el7.noarch
openshift-ansible-3.11.92-1.git.0.f2fade7.el7.noarch
ansible-2.6.15-1.el7ae.noarch

# ansible --version
ansible 2.6.15
  config file = /etc/ansible/ansible.cfg
  configured module search path = [u'/root/.ansible/plugins/modules', u'/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/lib/python2.7/site-packages/ansible
  executable location = /bin/ansible
  python version = 2.7.5 (default, Sep 12 2018, 05:31:16) [GCC 4.8.5 20150623 (Red Hat 4.8.5-36)]

How reproducible:
Every time

Steps to Reproduce:
1. Set var template_service_broker_selector={"node-role.kubernetes.io/infra": "true"} on inventory
2. Run the openshift-service-catalog/config.yml playbook
3. Check the daemonset on the project:
  # oc get all -n openshift-template-service-broker

Actual results:
Daemonset will have 2 nodeSelectors, pods won't start and the playbook will fail on TASK [template_service_broker : Verify that TSB is running]

Expected results:
Use only the value set for 'template_service_broker_selector' variable

Additional info:
Issue seems to be:

 # grep -e 'Apply template file' -A7 /usr/share/ansible/openshift-ansible/roles/template_service_broker/tasks/deploy.yml
- name: Apply template file
  shell: >
    {{ openshift_client_binary }} process --config={{ mktemp.stdout }}/admin.kubeconfig
    -f "{{ mktemp.stdout }}/{{ __tsb_template_file }}" -n openshift-template-service-broker
    --param API_SERVER_CONFIG="{{ config['content'] | b64decode }}"
    --param IMAGE="{{ template_service_broker_image }}"
    --param NODE_SELECTOR={{ {'node-role.kubernetes.io/master':'true'} | to_json | quote }}
    | {{ openshift_client_binary }} apply --config={{ mktemp.stdout }}/admin.kubeconfig -f -