chore(wordpress): update image docker.io/bitnamisecure/wordpress digest to a1c720b (#48486)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| docker.io/bitnamisecure/wordpress | digest | `4965c05` → `a1c720b` |

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charts/stable/wordpress/Chart.yaml

@@ -43,5 +43,5 @@ sources:
   - https://hub.docker.com/r/bitnamisecure/wordpress
   - https://www.wordpress.org
 type: application
-version: 13.6.3
+version: 13.6.4
 

charts/stable/wordpress/values.yaml

@@ -2,7 +2,7 @@
 image:
   repository: docker.io/bitnamisecure/wordpress
   pullPolicy: IfNotPresent
-  tag: latest@sha256:4965c05784fb975b2403eb8f4841d0d43c065f973dd1658ccce68735a6a47e1a
+  tag: latest@sha256:a1c720b711ddc01401d07b868906f67c4be49ca81e32d65c54fe9d208ec44f81
 securityContext:
   container:
     readOnlyRootFilesystem: false