Fixes -'s to _'s for consistency with other modules

test/aws-us-gov/mdr-test-c2/020-transit-gateway-interconnect-vpn/terragrunt.hcl

@@ -8,7 +8,7 @@ locals {
 
 terraform {
   # Double slash is intentional and required to show root of modules
-  source = "git@github.mdr.defpoint.com:mdr-engineering/xdr-terraform-modules.git//base/transit-gateway-interconnect-vpn?ref=v0.3.1"
+  source = "git@github.mdr.defpoint.com:mdr-engineering/xdr-terraform-modules.git//base/transit_gateway_interconnect_vpn?ref=v0.3.3"
 }
 
 dependency "transit-gateway-hub" {