adding RENXT Documents connector

[Blackbaud-BenLambert]

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[sriyen-msft]

@Blackbaud-BenLambert Apologies for the delay in response. We had a few certification and deployment freezes in the last month and have a high number of submissions in our pipeline. Hence reviewing your PR was delayed. I have approved it now. Please upload the latest artifacts in the ISV Studio to move forward in the certification. Thanks.