deps: update camunda-platform-images

| datasource | package                                     | from   | to     |
| ---------- | ------------------------------------------- | ------ | ------ |
| docker     | registry.camunda.cloud/keycloak-ee/keycloak | 26.5.6 | 26.6.1 |
| docker     | registry.camunda.cloud/vendor-ee/postgresql | 18.3.0 | 18.4.0 |

Author: renovate[bot]

charts/camunda-platform-8.9/values-enterprise.yaml

@@ -28,7 +28,7 @@ identityPostgresql:
   image:
     registry: registry.camunda.cloud
     repository: vendor-ee/postgresql
-    tag: 18.3.0-debian-12-r0
+    tag: 18.4.0-debian-12-r0
     pullSecrets:
       - name: registry-camunda-cloud
 
@@ -50,7 +50,7 @@ identityKeycloak:
   image:
     registry: registry.camunda.cloud
     repository: keycloak-ee/keycloak
-    tag: 26.5.6
+    tag: 26.6.1
     pullSecrets:
       - name: registry-camunda-cloud
 
@@ -65,7 +65,7 @@ identityKeycloak:
     image:
       registry: registry.camunda.cloud
       repository: vendor-ee/postgresql
-      tag: 18.3.0-debian-12-r0
+      tag: 18.4.0-debian-12-r0
       pullSecrets:
         - name: registry-camunda-cloud
 
@@ -87,7 +87,7 @@ webModelerPostgresql:
   image:
     registry: registry.camunda.cloud
     repository: vendor-ee/postgresql
-    tag: 18.3.0-debian-12-r0
+    tag: 18.4.0-debian-12-r0
     pullSecrets:
       - name: registry-camunda-cloud