Update K8s images in executors to v6.9.391

Author: DaedalusG

components/executors/k8s/executor.Deployment.yaml

@@ -29,7 +29,7 @@ spec:
       serviceAccountName: executor
       containers:
         - name: executor
-          image: index.docker.io/sourcegraph/executor-kubernetes:6.2.1106@sha256:6b9967ae0a57ccd54bb85347929692f709f921880e1ee4366f5114d8d6f0b59c
+          image: us-docker.pkg.dev/sourcegraph-images/internal/executor-kubernetes:6.9.391@sha256:37108549705fda805e7b1beda870893063f299c67a8f11552dbf24f75ccc7abd
           imagePullPolicy: Always
           livenessProbe:
             exec: