fix: the command is "secret"

.env.sample

@@ -57,8 +57,8 @@ COMPOSE_FILE="compose.yml"
 
 # Set wildcards = 1, and uncomment compose_file to enable.
 # Create your certs elsewhere and add them like:
-# abra app secrets insert {myapp.example.coop} ssl_cert v1 "$(cat /path/to/fullchain.pem)"
-# abra app secrets insert {myapp.example.coop} ssl_key v1 "$(cat /path/to/privkey.pem)"
+# abra app secret insert {myapp.example.coop} ssl_cert v1 "$(cat /path/to/fullchain.pem)"
+# abra app secret insert {myapp.example.coop} ssl_key v1 "$(cat /path/to/privkey.pem)"
 #WILDCARDS_ENABLED=1
 #SECRET_WILDCARD_CERT_VERSION=v1
 #SECRET_WILDCARD_KEY_VERSION=v1