JIT

gh-131798: Narrow the return type of `_FORMAT_SIMPLE` and `_FORMAT_WITH_SPEC` to `str` #6404

Job	Run time
x86_64-apple-darwin/clang (Release)	34m 40s
aarch64-pc-windows-msvc/msvc (Debug)	26m 31s
x86_64-unknown-linux-gnu/gcc (Release)	7m 47s
aarch64-unknown-linux-gnu/gcc (Release)	6m 26s
x86_64-apple-darwin/clang (Debug)	51m 7s
aarch64-apple-darwin/clang (Debug)	14m 34s
aarch64-apple-darwin/clang (Release)	13m 37s
x86_64-pc-windows-msvc/msvc (Release)	15m 56s
Interpreter (Debug)	12m 45s
JIT with tail calling interpreter	3m 38s
JIT without optimizations (Debug)	3m 13s
x86_64-unknown-linux-gnu/gcc (Debug)	13m 58s
Free-Threaded (Debug)	3m 13s
i686-pc-windows-msvc/msvc (Release)	15m 9s
aarch64-unknown-linux-gnu/gcc (Debug)	8m 57s
aarch64-pc-windows-msvc/msvc (Release)	20m 49s
i686-pc-windows-msvc/msvc (Debug)	26m 5s
x86_64-pc-windows-msvc/msvc (Debug)	30m 14s
	5h 8m 39s

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