switch to generated remote jdk configs and bump versions

[gitramirez]

Note

Medium Risk
Changes the source and registration of toolchain JDK repositories and updates all pinned JDK binaries; mistakes could break toolchain resolution or CI due to bad URLs/hashes/strip prefixes.

Overview
Updates remote JDK provisioning to be generated from a single source of truth: adds java/bazel/repositories_util.bzl (release matrix + URL/strip_prefix generation) and a java/bazel:dump_remote_jdk_configs genrule, then replaces the hand-written remote_jdk*_repos definitions in java/repositories.bzl with a generated _REMOTE_JDK_CONFIGS_LIST and shared registration logic.

Bumps the pinned remote JDK versions (notably Zulu JDK 8/11/17/21) and refreshes URLs/sha256/strip_prefix values, and adds a new test/check_remote_jdk_configs_test (wired into CI on Ubuntu) that downloads each configured archive to validate hashes and strip_prefix.

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Cursor Bugbot has reviewed your changes and found 1 potential issue.

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Dict iteration missing .items() and nested loop

High Severity

REMOTE_JDK_CONFIGS is a dict (from _make_version_to_remote_jdks() which returns {}), but for __, item in REMOTE_JDK_CONFIGS: iterates over the dict's keys (strings "8", "11", etc.) and tries to unpack each into two variables. This will crash on the first key "8" since a single-character string can't be unpacked into two variables. Even for two-character keys like "11", item would be the character "1", not a config struct. The iteration needs .items() and a nested loop over the list values to access individual config structs.