minor #11058 Update fortrabbit.rst (CodyFortenberry)

This PR was merged into the 3.4 branch.

Discussion
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Update fortrabbit.rst

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Commits
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5b4e7f0 Update fortrabbit.rst

Author: javiereguiluz

deployment/fortrabbit.rst

@@ -78,7 +78,7 @@ Create the file ``app/config/config_prod_secrets.php`` with the following
 contents::
 
     // get the path to the secrects.json file
-    $secrets = getenv("APP_SECRETS")
+    $secrets = getenv("APP_SECRETS");
     if (!$secrets) {
         return;
     }