docs(cognito): Update README.md (#9744)

[Problem]
CDK documentation for Cognito specifies an incorrect property (accountRecoverySettings -> accountRecovery)

[Solution]
Updated the documentation to use the correct property.


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packages/@aws-cdk/aws-cognito/README.md

@@ -283,7 +283,7 @@ can either be email and/or SMS. Read more at [Recovering User Accounts](https://
 ```ts
 new UserPool(this, 'UserPool', {
   ...,
-  accountRecoverySettings: AccountRecovery.EMAIL_ONLY,
+  accountRecovery: AccountRecovery.EMAIL_ONLY,
 })
 ```