chore: dump version to 2.2.6

Signed-off-by: Rory Z <16801068+Rory-Z@users.noreply.github.com>

RELEASE.md

@@ -1,6 +1,6 @@
 # Release Note 🍻
 
-EMQX Operator 2.2.5 has been released.
+EMQX Operator 2.2.6 has been released.
 
 ## Supported version
 + apps.emqx.io/v2beta1
@@ -17,7 +17,7 @@ EMQX Operator 2.2.5 has been released.
 
 + `apps.emqx.io/v2beta1 EMQX`.
 
-  + Fix the issue of the EMQX Operator will crash when the `.spec.config.data` of the EMQX customer resource is not a valid HOCON string
+  + Fix the issue of sometimes the new EMQX pod can't start, including scale-up and blue-green deployment.
 
 ## How to install/upgrade EMQX Operator 💡
 
@@ -29,7 +29,7 @@ helm repo update
 helm upgrade --install emqx-operator emqx/emqx-operator \
   --namespace emqx-operator-system \
   --create-namespace \
-  --version 2.2.5
+  --version 2.2.6
 kubectl wait --for=condition=Ready pods -l "control-plane=controller-manager" -n emqx-operator-system
 ```