chore(mariadb): update image docker.io/bitnamisecure/mariadb digest to a1b946e (#49972)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| docker.io/bitnamisecure/mariadb | digest | `946c00e` → `a1b946e` |

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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: 18.6.1
+version: 18.6.2
 

charts/stable/mariadb/values.yaml

@@ -2,7 +2,7 @@
 image:
   repository: docker.io/bitnamisecure/mariadb
   pullPolicy: IfNotPresent
-  tag: latest@sha256:946c00ed95bbe1c1df5c3f979db1a35344e4e25ed112110fd7db82ee9c505564
+  tag: latest@sha256:a1b946eaefe2da489f518daf6b00493b873b4593f3fe650658725a0a799f5e7b
 workload:
   main:
     podSpec: