apps/meet: force mail port to string

https://github.com/fluxcd/flux2/issues/4154

apps/meet/calcom/calcom-keys.yaml

@@ -10,7 +10,7 @@ stringData:
   CALENDSO_ENCRYPTION_KEY: "${calendso_key}"
   EMAIL_FROM: "${outgoing_mail_from_address}"
   EMAIL_SERVER_HOST: "${outgoing_mail_smtp_host}"
-  EMAIL_SERVER_PORT: "${outgoing_mail_smtp_port}"
+  EMAIL_SERVER_PORT: "!!str ${outgoing_mail_smtp_port}"
   EMAIL_SERVER_USER: "${outgoing_mail_smtp_user}"
   EMAIL_SERVER_PASSWORD: "${outgoing_mail_smtp_password}"
   # email_enabled: "${outgoing_mail_enabled}"