OCPBUGS-54949:adding the missing double quote in example

Author: aravipra

modules/secrets-store-vault.adoc

@@ -284,7 +284,7 @@ spec:
     objects:  |
       - secretPath: "secret/data/example1"
         objectName: "testSecret1"
-        secretKey: "testSecret1
+        secretKey: "testSecret1"
 ----
 <1> Specify the name for the secret provider class.
 <2> Specify the namespace for the secret provider class.