Automatic merge from submit-queue

[Federation] Add integration test for secrets

This PR adds an integration test for secrets that:

 - performs create/read/update/delete on federation resources and validates that the changes are propagated to member clusters.  
 - uses an abstraction layer (fixture and adapter) to minimize the code required to support each federated type
   - It should be possible to replace a test-specific adapter with a runtime adapter in the future (as per #41050)
 - reuses fixture (federation api and clusters) across different resource types to minimize setup overhead
   - on a fast machine, setup takes ~4s, and validating each type takes ~2s  
 - uses the [Subtest feature added in Go 1.7](https://blog.golang.org/subtests) to allow the test for a specific controller to be run in isolation
   - ``make test-integration WHAT="federation  -test.run=TestFederationCRUD/secret"``

Once this PR merges the test can be extended to target other federated types.

This PR targets #40705

cc: @kubernetes/sig-federation-pr-reviews @derekwaynecarr