build(deps-major): update mysql docker tag to v9 (#235)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| mysql | major | `8.4` → `9.6` |

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docker-compose.yml

@@ -2,7 +2,7 @@ version: '3.9'
 
 services:
   mysql:
-    image: mysql:8.4@sha256:7fcf7bcd3fa703ff23a2b998e4ed9077e5db570bcc4468459902e33b23d2841d
+    image: mysql:9.6@sha256:db32c8ec843c042a728efb0ac7aa814d6f010eaac8923e20ae0a849d09c5baf8
     container_name: grafanactl-mysql
     restart: unless-stopped
     environment: