JIT

gh-154535: Fix crash when a contextvars.Context iterator is shared between threads #7027

Job	Run time
Interpreter (Debug)	13m 27s
Free-Threaded (Debug)	3m 53s
JIT with tail calling interpreter	3m 38s
aarch64-unknown-linux-gnu/gcc (Debug)	8m 56s
x86_64-unknown-linux-gnu/gcc (Release)	8m 58s
x86_64-unknown-linux-gnu/gcc (Debug)	14m 36s
x86_64-apple-darwin/clang (Debug)	29m 8s
aarch64-apple-darwin/clang (Debug)	17m 19s
JIT with stress testing (Debug)	4m 32s
x86_64-apple-darwin/clang (Release)	24m 11s
aarch64-pc-windows-msvc/msvc (Release)	19m 14s
aarch64-unknown-linux-gnu/gcc (Release)	6m 17s
x86_64-pc-windows-msvc/msvc (Debug)	28m 37s
JIT without optimizations (Debug)	3m 56s
i686-pc-windows-msvc/msvc (Release)	17m 51s
aarch64-pc-windows-msvc/msvc (Debug)	29m 1s
aarch64-apple-darwin/clang (Release)	16m 51s
i686-pc-windows-msvc/msvc (Debug)	24m 6s
x86_64-pc-windows-msvc/msvc (Release)	16m 2s
	4h 50m 33s

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