docs(cognito): wrong default value for UserPoolClient authFlows (#26700)

When `authFlows` is not defined `UserPoolClient` will support ALLOW_REFRESH_TOKEN_AUTH, ALLOW_USER_SRP_AUTH, and ALLOW_CUSTOM_AUTH.

[Link](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-cognito-userpoolclient.html#cfn-cognito-userpoolclient-explicitauthflows) to CFN docs.

Closes #26680.

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*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

Author: lpizzinidev

packages/aws-cdk-lib/aws-cognito/lib/user-pool-client.ts

@@ -222,7 +222,7 @@ export interface UserPoolClientOptions {
   /**
    * The set of OAuth authentication flows to enable on the client
    * @see https://docs.aws.amazon.com/cognito/latest/developerguide/amazon-cognito-user-pools-authentication-flow.html
-   * @default - all auth flows disabled
+   * @default - If you don't specify a value, your user client supports ALLOW_REFRESH_TOKEN_AUTH, ALLOW_USER_SRP_AUTH, and ALLOW_CUSTOM_AUTH.
    */
   readonly authFlows?: AuthFlow;