Migrate HPA v1 to v2beta2 (#2421)

* Migrate HPA v1 to v2beta2
HPA v2beta2 is defined and supported from 1.19+ onwards.
Also HPA v2 is stable from 1.23 onwards. As we support 1.19+
onwards using HPA v2beta2.
This change is base for custom metrics support we want to add
later by modifying Function spec.
* Add unit tests for hpa operations
* Use constants instead of strings

Signed-off-by: Sanket Sudake <sanketsudake@gmail.com>

pkg/utils/otel/attributes.go

@@ -6,7 +6,8 @@ import (
 	"go.opentelemetry.io/otel/attribute"
 	"go.opentelemetry.io/otel/trace"
 	appsv1 "k8s.io/api/apps/v1"
-	asv1 "k8s.io/api/autoscaling/v1"
+	asv2beta2 "k8s.io/api/autoscaling/v2beta2"
+
 	apiv1 "k8s.io/api/core/v1"
 
 	fv1 "github.com/fission/fission/pkg/apis/core/v1"
@@ -74,7 +75,7 @@ func GetAttributesForDeployment(deployment *appsv1.Deployment) []attribute.KeyVa
 	}
 }
 
-func GetAttributesForHPA(hpa *asv1.HorizontalPodAutoscaler) []attribute.KeyValue {
+func GetAttributesForHPA(hpa *asv2beta2.HorizontalPodAutoscaler) []attribute.KeyValue {
 	if hpa == nil {
 		return []attribute.KeyValue{}
 	}