Fix "same major version" check logic

[fmeum]

This was introduced in 2db269a, but unintentionally checked for full equality of major, minor and patch version rather than just the major version.

[fmeum]

FYI @dzbarsky

[brentleyjones]

Do we want a unit test? 😅

[fmeum]

Do we want a unit test? 😅

We do, but it's also pretty difficult to write one with the current setup. I will keep a mental note to refactor this logic now that we have more complex operators.

[timothyg-stripe]

Oops, thank you!