JIT

gh-131798: Narrow the return type of `_FORMAT_SIMPLE` and `_FORMAT_WITH_SPEC` to `str` #5953

Job	Run time
aarch64-apple-darwin/clang (Release)	12m 24s
x86_64-apple-darwin/clang (Release)	25m 43s
aarch64-apple-darwin/clang (Debug)	14m 32s
Interpreter (Debug)	12m 24s
x86_64-unknown-linux-gnu/gcc (Release)	9m 10s
x86_64-apple-darwin/clang (Debug)	43m 59s
x86_64-unknown-linux-gnu/gcc (Debug)	14m 27s
JIT without optimizations (Debug)	3m 29s
i686-pc-windows-msvc/msvc (Release)	15m 7s
aarch64-unknown-linux-gnu/gcc (Debug)	9m 32s
JIT with tail calling interpreter	4m 59s
x86_64-pc-windows-msvc/msvc (Debug)	25m 35s
i686-pc-windows-msvc/msvc (Debug)	29m 53s
aarch64-unknown-linux-gnu/gcc (Release)	7m 2s
Free-Threaded (Debug)	3m 49s
aarch64-pc-windows-msvc/msvc (Debug)	26m 42s
x86_64-pc-windows-msvc/msvc (Release)	15m 47s
aarch64-pc-windows-msvc/msvc (Release)	18m 49s
	4h 53m 23s

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