fix syntax

Author: osterman

deploy/releases/app.yaml

@@ -66,7 +66,7 @@ releases:
             '{{ requiredEnv "COLOR" }}.{{ env "APP_HOSTNAME" }}': /
           tls:
               ### Optional: ATLANTIS_TLS_SECRET_NAME;
-            - secretName: '{{ env "APP_TLS_SECRET_NAME" | default "example-{{ requiredEnv "COLOR" }}-server-tls" }}'
+            - secretName: '{{ env "APP_TLS_SECRET_NAME" | default (requiredEnv "COLOR" | printf "example-%s-server-tls") }}'
               hosts:
               ### Required: APP_HOSTNAME;
               - '{{ requiredEnv "COLOR" }}.{{ env "APP_HOSTNAME" }}'