Remove WIP notes

[DinithiDiaz]

Description

Several pages in the documentation space are marked as WIP (Work in Progress). These notes had been added around 2020/2021 and are also present in the EI and APIM documentation. We need to remove the WIP notes after updating these pages with accurate content.

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Examples:

• https://mi.docs.wso2.com/en/4.3.0/learn/examples/data-integration/distributed-trans-data-service/
• https://mi.docs.wso2.com/en/4.3.0/learn/examples/working-with-transactions/
• https://mi.docs.wso2.com/en/4.3.0/learn/examples/endpoint-examples/using-static-recepient-list-endpoints/