ci: update v1.20 testing to OCP 4.21 per review

Author: E2E Test Bot

ci-operator/config/redhat-developer/gitops-operator/redhat-developer-gitops-operator-v1.20__v4.19.yaml

@@ -1,10 +1,10 @@
 base_images:
   cli:
-    name: "4.14"
+    name: "4.21"
     namespace: ocp
     tag: cli
   operator-sdk:
-    name: "4.20"
+    name: "4.21"
     namespace: origin
     tag: operator-sdk
 build_root:
@@ -35,12 +35,12 @@ operator:
 releases:
   initial:
     integration:
-      name: "4.14"
+      name: "4.21"
       namespace: ocp
   latest:
     integration:
       include_built_images: true
-      name: "4.14"
+      name: "4.21"
       namespace: ocp
 resources:
   '*':
@@ -132,4 +132,4 @@ zz_generated_metadata:
   branch: v1.20
   org: redhat-developer
   repo: gitops-operator
-  variant: v4.14
+  variant: v4.21