Add a conditional to declare secrets

This permit to push the modification, then open a ticket to add the secret,
and deploy fine in staging if there is no integration with github.

roles/openshift-apps/coreos/templates/buildconfig.yml

@@ -20,6 +20,12 @@ spec:
         kind: ImageStreamTag
         name: s2i-golang:latest
   triggers:
+{% if coreos_github_secret is defined %}
+  - type: GitHub
+    github:
+      secret: "{{ coreos_github_secret }}"
+{% endif %}
+
 # TODO add that once it is clear on how to store the secret
 #  - type: GitHub
 #    github:

roles/openshift-apps/silverblue/templates/buildconfig.yml

@@ -20,9 +20,10 @@ spec:
         kind: ImageStreamTag
         name: s2i-golang:latest
   triggers:
-# TODO add that once it is clear on how to store the secret
-#  - type: GitHub
-#    github:
-#      secret: "some_coreos_github_secret"
+{% if silverblue_github_secret is defined %}
+  - type: GitHub
+    github:
+      secret: "{{ silverblue_github_secret }}"
+{% endif %}
   - type: ConfigChange
   - type: ImageChange