JIT

GH-140479: Update JIT builds to use LLVM 21 #4294

Job	Run time
Interpreter (Debug)	10m 16s
Free-Threaded (Debug) (21)	15m 0s
JIT with tail calling interpreter (21)	3m 25s
JIT without optimizations (Debug) (21)	15m 2s
x86_64-pc-windows-msvc/msvc (Debug)	19m 17s
i686-pc-windows-msvc/msvc (Debug)	21m 16s
aarch64-pc-windows-msvc/msvc (Release)	18m 47s
aarch64-pc-windows-msvc/msvc (Debug)	23m 38s
x86_64-pc-windows-msvc/msvc (Release)	11m 32s
x86_64-unknown-linux-gnu/gcc (Debug)	12m 26s
i686-pc-windows-msvc/msvc (Release)	11m 39s
x86_64-apple-darwin/clang (Release)	32m 28s
aarch64-apple-darwin/clang (Release)	10m 38s
aarch64-unknown-linux-gnu/gcc (Debug)	24m 43s
aarch64-unknown-linux-gnu/gcc (Release)	5m 45s
x86_64-apple-darwin/clang (Debug)	31m 15s
aarch64-apple-darwin/clang (Debug)	15m 11s
x86_64-unknown-linux-gnu/gcc (Release)	6m 54s
	4h 49m 12s

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