[`flake8-pyi`] Implement autofix and handle nested unions with single element (`PYI041` , `PYI055`) #35377

Job	Run time
pre-commit	1m 3s
cargo fmt	17s
mkdocs	2m 38s
Determine changes	9s
python package	1m 20s
benchmarks	2m 49s
cargo build (release)	2m 51s
cargo build (msrv)	2m 49s
cargo clippy	1m 47s
cargo fuzz	32s
cargo shear	24s
cargo test (linux)	2m 49s
cargo test (wasm)	1m 26s
cargo test (windows)	2m 33s
formatter instabilities and black similarity	0s
test scripts	1m 0s
ecosystem	1s
Fuzz the parser	1s
test ruff-lsp	1s
	24m 30s

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