The return type of ktesting.NewTestContext is now a TContext. Code
which combined it WithCancel often didn't compile anymore (cannot overwrite
ktesting.TContext with context.Context). This is a good thing because all of
that code can be simplified to let ktesting handle the cancelation.
the serviceAccountController controller used by the tests must wait for the caches to sync
since the tests don't check /readyz there is no way
the tests can tell it is safe to call the server and requests won't be rejected
* fix duplicated imports of api/core/v1
* fix duplicated imports of client-go/kubernetes
* fix duplicated imports of rest code
* change import name to more reasonable
Automatic merge from submit-queue (batch tested with PRs 67707, 62420). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
svcacct: support jose.OpaqueSigner and push errors to token generator creation
```release-note
NONE
```
Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
Externalize serviceaacount admission controller
ref: #66680
this pull externalizes serviceaccount admission controller in which secret & serviceaccount informers will be completely replaced.
/sig api-machinery
**Release note**:
```release-note
NONE
```
Right now if a JWT for an unknown issuer, for any subject hits the
serviceaccount token authenticator, we return a errors as if the token
was meant for us but we couldn't find a key to verify it. We should
instead return nil, false, nil.
This change helps us support multiple service account token
authenticators with different issuers.
Automatic merge from submit-queue (batch tested with PRs 53592, 52562, 55175, 55213). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
Check RegisterMetricAndTrackRateLimiterUsage error when starting BootstrapSigner & TokenCleaner controllers
**What this PR does / why we need it**:
Prevent `BootstrapSigner` and `TokenCleaner` controllers to start if `metrics.RegisterMetricAndTrackRateLimiterUsage` returns an error.
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: complements #53571
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
