chore(mariadb): update image docker.io/bitnamisecure/mariadb digest to a6aa715 (#47429)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| docker.io/bitnamisecure/mariadb | digest | `1086b43` → `a6aa715` |

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charts/stable/mariadb/Chart.yaml

@@ -40,5 +40,5 @@ sources:
   - https://hub.docker.com/r/bitnamisecure/mariadb
   - https://mariadb.org
 type: application
-version: 18.1.1
+version: 18.1.2
 

charts/stable/mariadb/values.yaml

@@ -2,7 +2,7 @@
 image:
   repository: docker.io/bitnamisecure/mariadb
   pullPolicy: IfNotPresent
-  tag: latest@sha256:1086b43c2b4ce31c1d714bc166b7eb5771f787b91232ea37d719473c838c6917
+  tag: latest@sha256:a6aa7154f5e7c08f2515989e5810426dac9da633fb24785d525d75bdbd9cb23f
 workload:
   main:
     podSpec: