chore: restore production release gate

packages/mail/src/index.ts

@@ -117,7 +117,7 @@ export function defineSealedMailCredentials(options: SealedMailCredentialsOption
     const secret = process.env[env];
     if (!secret)
       throw new Error(`${env} is not set; it is required to seal mail credentials at rest.`);
-    let length = 0;
+    let length: number;
     try {
       length = atob(secret).length;
     } catch {