[WIP] authhelper: dynamically add/remove authentication and session mgmt methods

[forgedhallpass]

• related PR on ZAP: Allow to add/remove authentication and session management methods zaproxy#7857

[forgedhallpass]

@thc202 this is not WIP, because the work is done. I have tested it locally.

The builds are failing, because these changes are dependent on the PR referenced in the description, hence the initial title "integration" of those changes from ZAP into this repository.

[thc202]

It's WIP, it depends on unreleased core changes.

[forgedhallpass]

It's WIP, it depends on unreleased core changes.

I see, I thought you have some labels to mark PRs that have a dependency. What I meant is that the work is done from my part.

[psiinon]

We cant merge any changes to zap-extensions that depend on unreleased zaproxy changes.
We can get around that using reflection and handling the possibility that someone will be using the current version of the core rather than the unreleased one.

[thc202]

That would be safer, since core will start throwing an exception.