RFR: 8255: Update toolchain and base images to support building with Java21 in docker

[Alex Macdonald]

On Tue, 10 Sep 2024 19:02:50 GMT, Martin Skarsaune <duke at openjdk.org> wrote:

> Getting this trying to build with docker from master:
> 
> 
> [ERROR] Failed to execute goal org.apache.maven.plugins:maven-toolchains-plugin:3.2.0:toolchain (default) on project missioncontrol: Cannot find matching toolchain definitions for the following toolchain types:
> [ERROR] jdk [ id='JavaSE-21' version='21' ]
> [ERROR] Please make sure you define the required toolchains in your ~/.m2/toolchains.xml file.
> [ERROR] -> [Help 1]

Marked as reviewed by aptmac (Reviewer).

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PR Review: https://git.openjdk.org/jmc/pull/585#pullrequestreview-2307591301