Fix parsing BigInt from str #4330

Job	Run time
test-debug 3.11	1m 0s
test-debug pypy3.10	1m 26s
test on ubuntu	2m 20s
test on macos	3m 14s
test 3.8	2m 6s
coverage	3m 0s
test on windows	5m 11s
test 3.9	2m 9s
rust benchmarks	3m 26s
test 3.10	2m 9s
test 3.11	2m 3s
test 3.12	2m 30s
lint	1m 5s
test pypy3.9	2m 39s
test pypy3.10	2m 31s
build-wasm-emscripten	2m 34s
test-pydantic-integration	1m 30s
build sdist	18s
build on ${{ matrix.os }} (${{ matrix.target }} - ${{ matrix.interpreter \|\| 'all' }}${{ (((matrix.os == 'linux') && format(' - {0}', (((matrix.manylinux == 'auto') && 'manylinux') \|\| matrix.manylinux))) \|\| '') }})	0s
build pgo-optimized on ${{ matrix.os }} / ${{ matrix.interpreter }}	0s
test build on ${{ matrix.target }}-${{ matrix.distro }}	0s
test build on ${{ matrix.os }}	0s
inspect-pypi-assets	0s
check	7s
release	0s
	41m 18s

Provide feedback