This step is only required if the Jamf Pro Signing Certificate was generated from Jamf Pro.
In Jamf Pro, go to Settings > Global > PKI Certificates > Management Certificate Template and click Download CA Cert.
Ensure the certificate will be saved with a .crt extension.
Double-click on the downloaded file and click Install Certificate.
Select the Local Machine option to add a certificate for all users and click Next.
Select the Place all certificates in the following store option, click Browse and ensure the certificate will be installed in Trusted Root Certification Authorities.