Add WebhookAuthenticator integration tests, expand unit tests

- Add WebhookAuthenticator unit tests, update generated code
- Add validateTLSNegotiation(), update tests
- Update validateTLSNegotiation, add unit tests, factor out helpers
- Update generated code

test/integration/concierge_webhookauthenticator_status_test.go

@@ -2,3 +2,9 @@
 // SPDX-License-Identifier: Apache-2.0
 
 package integration
+
+// TODO: for integration tests, not unit tests....
+// env.APIGroupSuffix for log messages/conditions when relevant, ie if "pinniped.dev" appears
+// env.CLIUpstreamOIDC.Issuer if a real endpoint is needed as we shouldn't actually make requests
+//   to example.com
+// goodEndpoint := "https://example.com"