AWS Endpoints and Packer

Hello,

Using Packer to build our AMIs but because of firewall policies beyond our control, we can’t perform IAM actions using standard AWS endpoints. However, we are allowed to hit FIPS IAM endpoints. Packer uses iam.amazonaws.com but we need for it to use iam-fips.amazonaws.com My question is, how do I configure Packer to use the FIPS endpoints?