Remove outdated kustomization files

execution/uc-application/kustomization.yaml

-apiVersion: kustomize.config.k8s.io/v1beta1
-kind: Kustomization
-
-commonLabels:
-  app: titan-ccp-aggregation
-
-# Use all resources to compose them into one file
-resources:
-  - aggregation-deployment.yaml
-  - aggregation-service.yaml
-  - service-monitor.yaml
-  - jmx-configmap.yaml

execution/uc-workload-generator/kustomization.yaml

-apiVersion: kustomize.config.k8s.io/v1beta1
-kind: Kustomization
-
-resources:
-  - workloadGenerator.yaml