Update dependency java-jdk to v21

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
java-jdk	uses-with	major	17 → 21

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Warning

Some dependencies could not be looked up. Check the Dependency Dashboard for more information.

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Configuration

📅 Schedule: (UTC)

• Branch creation
  • Between 12:00 AM and 03:59 AM, on the second Monday and fourth Monday of the month (* 0-3 * * 1#2,1#4)
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[codspeed]

Merging this PR will degrade performance by 16.93%

⚠️ Unknown Walltime execution environment detected

Using the Walltime instrument on standard Hosted Runners will lead to inconsistent data.

For the most accurate results, we recommend using CodSpeed Macro Runners: bare-metal machines fine-tuned for performance measurement consistency.

❌ 1 regressed benchmark
✅ 2061 untouched benchmarks
⏩ 503 skipped benchmarks¹

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	WallTime	scalar_subtract_neon	12.7 µs	15.3 µs	-16.93%

Tip

Investigate this regression by commenting @codspeedbot fix this regression on this PR, or directly use the CodSpeed MCP with your agent.

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_{Comparing renovate/java-jdk-21.x (ce495b8) with develop (1d61f89)}

Footnotes

1. 503 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[renovate]

Renovate Ignore Notification

Because you closed this PR without merging, Renovate will ignore this update. You will not get PRs for any future 21.x releases. But if you manually upgrade to 21.x then Renovate will re-enable minor and patch updates automatically.

If you accidentally closed this PR, or if you changed your mind: rename this PR to get a fresh replacement PR.