Improve assertions in test for python upgrade script #4149

Job	Run time
Build wheel and source distribution	30s
aarch64-unknown-linux-gnu (ubuntu-22.04)	3m 40s
x86_64-unknown-linux-gnu (ubuntu-22.04)	3m 59s
x86_64-unknown-linux-musl (ubuntu-22.04)	4m 14s
powerpc64le-unknown-linux-gnu (ubuntu-22.04)	3m 44s
x86_64-pc-windows-msvc (windows-2022)	7m 14s
i686-pc-windows-msvc (windows-2022)	7m 6s
aarch64-apple-darwin (macos-12)	6m 44s
x86_64-apple-darwin (macos-12)	7m 28s
Build Windows installers	1m 8s
Build macOS installer and sign/notarize artifacts	1m 19s
Publish release	0s
	47m 6s

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