Function getIdentityServiceConfig

Returns {
    identityService: {
        apiUrl: string;
        bucket: string;
        clientId: string;
        identityPoolId: string;
        poolId: string;
        region: string;
        registrationMethods: string[];
        transientBucket: string;
    } & { refreshTokenLifetime?: number };
} & {
    federatedSignIn?: {
        appClientId: string;
        signInRedirectUri: string;
        signOutRedirectUri: string;
        webDomain: string;
    } & { identityProvider?: string; refreshTokenLifetime?: number };
}