Fix Helm Chart DISCOVER_TOLERATION binding

Bind to `.Values.discover.toleration` (instead of `agent`)

Signed-off-by: Olivier Cloirec <5033885+clook@users.noreply.github.com>

cluster/charts/rook-ceph/templates/deployment.yaml

@@ -60,7 +60,7 @@ spec:
 {{- if .Values.discover }}
 {{- if .Values.discover.toleration }}
         - name: DISCOVER_TOLERATION
-          value: {{ .Values.agent.toleration }}
+          value: {{ .Values.discover.toleration }}
 {{- end }}
 {{- if .Values.discover.tolerationKey }}
         - name: DISCOVER_TOLERATION_KEY