Update dependency java to v21.0.8+9.0.LTS (#1465)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [java](https://adoptium.net) | patch | `21.0.7+6.0.LTS` ->
`21.0.8+9.0.LTS` |

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mise.toml

@@ -2,7 +2,7 @@
 "cargo:zizmor" = "1.9.0"
 "go:github.com/gohugoio/hugo" = "v0.148.1"
 "go:github.com/grafana/oats" = "0.3.2"
-java = "temurin-21.0.7+6.0.LTS"
+java = "temurin-21.0.8+9.0.LTS"
 lychee = "0.19.1"
 protoc = "31.1"