Remove Linux/s390x from jdk22u pipelines to float patch

[sxa]

As per PMC meeting this week we intend to float a patch on Linux/s390x including openjdk/jdk22u#137 which will require some manual effort to create a branch with the new tag after the official GA tag comes out. An s390x build without this patch will not be shippable, so we should not trigger it.

[github-actions]

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