Use the security group provided in the custom resource config

## Problem being solved
Currently the WSO2 custom resources creates a new security group when a network config is provided.

If the security groups is provided in the props, it is never added to the lambda, if it is not provided a new security group is created and added to the lambda

reference: https://github.com/flaviostutz/cdk-practical-constructs/blob/77a7f43917229c3beb3a081de8f6841e917faa11/lib/src/wso2/utils-cdk.ts#L44-L60

## Proposal
Start using the security groups provided in the `customResourceConfig` property in WSO2 custom resources.