JIT

gh-131798: Narrow the return type of `_FORMAT_SIMPLE` and `_FORMAT_WITH_SPEC` to `str` #6430

Job	Run time
Interpreter (Debug)	13m 9s
x86_64-unknown-linux-gnu/gcc (Release)	8m 46s
JIT without optimizations (Debug)	3m 49s
Free-Threaded (Debug)	3m 55s
x86_64-unknown-linux-gnu/gcc (Debug)	13m 36s
aarch64-unknown-linux-gnu/gcc (Release)	6m 33s
aarch64-apple-darwin/clang (Release)	14m 32s
x86_64-apple-darwin/clang (Release)	36m 6s
aarch64-unknown-linux-gnu/gcc (Debug)	8m 58s
aarch64-apple-darwin/clang (Debug)	20m 10s
x86_64-apple-darwin/clang (Debug)	30m 42s
JIT with tail calling interpreter	4m 45s
i686-pc-windows-msvc/msvc (Debug)	25m 55s
x86_64-pc-windows-msvc/msvc (Release)	20m 5s
aarch64-pc-windows-msvc/msvc (Release)	18m 42s
x86_64-pc-windows-msvc/msvc (Debug)	27m 12s
aarch64-pc-windows-msvc/msvc (Debug)	25m 41s
i686-pc-windows-msvc/msvc (Release)	15m 31s
	4h 58m 7s

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