"Upload license key" displays in customer's control panel despite disabled in corresponding Plesk configuration.
The incorrect behavior described was caused by the software issue #CCU-13867. THe fix is planned to be included in one of the future product updates.
Contact your Technical Account Manager or PTA team (firstname.lastname@example.org) to track the status of the issue.
After Plesk is provisioned, synchronize the configuration manually in PCP > Plesk in VPS > Plesk Configurations > Click "Synchronize Plesk Instances" next to the required confiuration name