chore: Add some empty dir volume mounts for the application controller (

#19474)

Closes #19474

Kube cache couldn't be used on read-only root file system leading to errors as revealed with `--gloglevel` equal to 6.
Create an empty dir mount for `/tmp` and override `KUBECACHEDIR` to be in `/tmp`.

Signed-off-by: Andrii Korotkov <[email protected]>

manifests/base/application-controller/argocd-application-controller-statefulset.yaml

@@ -208,6 +208,8 @@ spec:
               name: argocd-cmd-params-cm
               key: controller.ignore.normalizer.jq.timeout
               optional: true
+        - name: KUBECACHEDIR
+          value: /tmp/kubecache
         image: quay.io/argoproj/argocd:latest
         imagePullPolicy: Always
         name: argocd-application-controller
@@ -236,6 +238,8 @@ spec:
           mountPath: /home/argocd
         - name: argocd-cmd-params-cm
           mountPath: /home/argocd/params
+        - name: argocd-application-controller-tmp
+          mountPath: /tmp
       serviceAccountName: argocd-application-controller
       affinity:
         podAntiAffinity:
@@ -255,6 +259,8 @@ spec:
       volumes:
       - emptyDir: {}
         name: argocd-home
+      - emptyDir: {}
+        name: argocd-application-controller-tmp
       - name: argocd-repo-server-tls
         secret:
           secretName: argocd-repo-server-tls