JIT

gh-131798: Narrow the return type of `_FORMAT_SIMPLE` and `_FORMAT_WITH_SPEC` to `str` #5783

Job	Run time
JIT with tail calling interpreter	4m 11s
Interpreter (Debug)	11m 33s
x86_64-apple-darwin/clang (Release)	37m 40s
x86_64-unknown-linux-gnu/gcc (Release)	9m 6s
aarch64-apple-darwin/clang (Debug)	16m 43s
aarch64-unknown-linux-gnu/gcc (Debug)	9m 7s
x86_64-apple-darwin/clang (Debug)	32m 59s
aarch64-unknown-linux-gnu/gcc (Release)	7m 27s
x86_64-unknown-linux-gnu/gcc (Debug)	14m 15s
Free-Threaded (Debug)	4m 1s
JIT without optimizations (Debug)	3m 40s
x86_64-pc-windows-msvc/msvc (Debug)	28m 38s
x86_64-pc-windows-msvc/msvc (Release)	14m 57s
aarch64-pc-windows-msvc/msvc (Release)	22m 24s
aarch64-apple-darwin/clang (Release)	11m 23s
i686-pc-windows-msvc/msvc (Debug)	24m 21s
i686-pc-windows-msvc/msvc (Release)	14m 47s
aarch64-pc-windows-msvc/msvc (Debug)	24m 47s
	4h 51m 59s

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