Error during VSTO install - Add additional certificate install instructions

[notdodgeball]

The VSTO version install fails with:

certificate used to sign the deployment manifest for Excel Addin Script Help or its location is not trusted

For anyone who may have the same issue, the workaround is to add the .pfx file needs to be added to the Trusted Publishers and Trusted Root Certification Authorities per

https://stackoverflow.com/questions/59440211/test-certificate-not-trusted

or using the certlm.msc tool.