New gitUsernamePassword binding only accounts for a single set of credentials.
Often there are different set of credentials required for different git locations.
Examples would be Go Modules, Terraform Modules and other that are using Git for dependency management. If the current repository we are building have dependencies on other repositories - we need read-write git credentials to the current repository (so we could publish tags, for example) while we need read-only set of credentials to everything else for fetching dependencies.
If this binding currently implemented as AskPass helper - an easy fix would be to accept additional parameter in the binding that'd tell the location the binding is for.