Add support for credential helpers for custom registries

[harrhp]

Is your feature request related to a problem? Please describe.
I need a way to authenticate to private registry via credential helper when pulling images. I have 2 private registries in ~/docker/.config.json that use bat files to provide credential. I don't know credentials in advance to just do docker login so i need to use helpers. Right now i can't pull images with this setup

Describe the solution you'd like
I think there should be another implementation of IAuthenticationProvider that implements credential helpers protocol described in the link below

Describe alternatives you've considered
i didn't find any solution

Additional context
https://docs.docker.com/engine/reference/commandline/login/#credential-helpers
I use version 1.6.0-beta.2226

[HofmeisterAn]

I added the class CredsHelperProvider in advance:

https://github.com/HofmeisterAn/dotnet-testcontainers/blob/ba7d87befb0ece496d94ec9f350d503a264a372c/src/DotNet.Testcontainers/Builders/CredsHelperProvider.cs#L6-L19

But I don't know exactly how the credential helpers work. I haven't looked into the docs, etc. Maybe, someone else can add the implementation. Or I need to do some researches first.

[HofmeisterAn]

We'll publish this change as soon as we update the NuGet feed configuration.

[HofmeisterAn]

Published in 1.7.0-beta.2530372824.