Set registry tls version to 1.2

when internal tls enabled set min version of registry to 1.2

Signed-off-by: DQ <dengq@vmware.com>

make/photon/prepare/templates/registry/config.yml.jinja

@@ -23,6 +23,8 @@ redis:
 http:
 {% if internal_tls.enabled %}
   addr: :5443
+  tls:
+    minimumtls: tls1.2
 {% else %}
   addr: :5000
 {% endif %}