Enable Workload Identity Federation to work with provider

[joekiller]

Presently the provider is limited to only work with GKE or Fleet Workload Identity pool providers. This PR ensures that the gcp provider may retrieve secrets on a cluster utilizing GOOGLE_APPLICATION_CREDENTIALS pointing to an audience pool provider backed by Workload Identity Federation with Kubernetes.

Included as well is a debug workflow which was instrumental in determining the most precise way to fix the absence of function and documentation updates to fill out points to help others utilize the secret driver backed by workload identity federation with kubernetes.

Fixes: #206

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[dargudear-google]

Thanks for the PR. Will take a look at this.

[joekiller]

I don't believe the e2e failure was directly due to the PR. seemed transient from the logs.

[dargudear-google]

Can you split the PR into 2?
each one will server one purpose.

[joekiller]

@dargudear-google by split, you mean one for the workload identity federation fix and one for the debug stuff?

[dargudear-google]

@dargudear-google by split, you mean one for the workload identity federation fix and one for the debug stuff?

Yes

[joekiller]

@dargudear-google I am closing this for #459 and #460.