xactfetch: Additional mounts for rbw sync

In order to sync the Bitwarden vault, `rbw` needs its configuration file
in `/etc/rbw` and access to writable ephemeral storage at `/tmp`.

xactfetch/xactfetch.yaml

@@ -41,6 +41,12 @@ spec:
             securityContext:
               readOnlyRootFilesystem: true
             volumeMounts:
+            - mountPath: /etc/rbw
+              name: xactfetch-rbw
+              readOnly: true
+            - mountPath: /tmp
+              name: tmp
+              subPath: tmp
             - mountPath: /var/lib/xactfetch
               name: xactfetch-data
               subPath: data