* Refactors the leafcert package to not have a dependency on agent/consul and agent/cache to avoid import cycles. This way the xds controller can just import the leafcert package to use the leafcert manager.
The leaf cert logic in the controller:
* Sets up watches for leaf certs that are referenced in the ProxyStateTemplate (which generates the leaf certs too).
* Gets the leaf cert from the leaf cert cache
* Stores the leaf cert in the ProxyState that's pushed to xds
* For the cert watches, this PR also uses a bimapper + a thin wrapper to map leaf cert events to related ProxyStateTemplates
Since bimapper uses a resource.Reference or resource.ID to map between two resource types, I've created an internal type for a leaf certificate to use for the resource.Reference, since it's not a v2 resource.
The wrapper allows mapping events to resources (as opposed to mapping resources to resources)
The controller tests:
Unit: Ensure that we resolve leaf cert references
Lifecycle: Ensure that when the CA is updated, the leaf cert is as well
Also adds a new spiffe id type, and adds workload identity and workload identity URI to leaf certs. This is so certs are generated with the new workload identity based SPIFFE id.
* Pulls out some leaf cert test helpers into a helpers file so it
can be used in the xds controller tests.
* Wires up leaf cert manager dependency
* Support getting token from proxytracker
* Add workload identity spiffe id type to the authorize and sign functions
---------
Co-authored-by: John Murret <john.murret@hashicorp.com>