chore: bump app-proxy version to 1.4020.0

Updates app-proxy to version 1.4020.0 which includes the removal of
Argo Rollouts installation capability (argo-platform#7045).

This aligns with the removal of argo-rollouts from the helm chart.

Author: dmaizel

charts/gitops-runtime/values.yaml

@@ -480,14 +480,14 @@ app-proxy:
           tag: 1.1.20-main
   image:
     repository: quay.io/codefresh/cap-app-proxy
-    tag: 1.4018.0
+    tag: 1.4020.0
     pullPolicy: IfNotPresent
   # -- Extra volume mounts for main container
   extraVolumeMounts: []
   initContainer:
     image:
       repository: quay.io/codefresh/cap-app-proxy-init
-      tag: 1.4018.0
+      tag: 1.4020.0
       pullPolicy: IfNotPresent
     command:
       - ./init.sh