[cozystack-controller] improve API tests (#1617)

Signed-off-by: Andrei Kvapil <kvapss@gmail.com>

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## What this PR does

Adds check also for core.cozystack.io group

### Release note

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```release-note
[cozystack-controller] improve API tests
```

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-->

## Summary by CodeRabbit

# Release Notes

* **Tests**
* Enhanced validation during installation to verify multiple API
services
* Expanded OpenAPI endpoint verification to include additional services

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

hack/e2e-install-cozystack.bats

@@ -118,7 +118,7 @@ EOF
 }
 
 @test "Check Cozystack API service" {
-  kubectl wait --for=condition=Available apiservices/v1alpha1.apps.cozystack.io --timeout=2m
+  kubectl wait --for=condition=Available apiservices/v1alpha1.apps.cozystack.io apiservices/v1alpha1.core.cozystack.io --timeout=2m
 }
 
 @test "Configure Tenant and wait for applications" {

hack/e2e-test-openapi.bats

@@ -9,6 +9,7 @@
 
 @test "Test OpenAPI v3 endpoint" {
   kubectl get -v7 --raw '/openapi/v3/apis/apps.cozystack.io/v1alpha1' > /dev/null
+  kubectl get -v7 --raw '/openapi/v3/apis/core.cozystack.io/v1alpha1' > /dev/null
 }
 
 @test "Test OpenAPI v2 endpoint (protobuf)" {