feat: extra secret

.env.sample

@@ -11,3 +11,4 @@ LETS_ENCRYPT_ENV=production
 
 SECRET_TEST_PASSWORD_VERSION=v1
 SECRET_TP_VERSION=v1 # length=10
+#SECRET_EXTRA_VERSION=v1

compose.extra_secret.yml

@@ -0,0 +1,12 @@
+---
+version: "3.8"
+
+services:
+  app:
+    secrets:
+      - extra
+
+secrets:
+  extra:
+    external: true
+    name: ${STACK_NAME}_extra_${SECRET_EXTRA_VERSION}