CartesianIndices gives different answer in Julia 1.6 and 1.5 for particular case

Some discussion here CartesianIndices (breaking?) change in 1.6.0-rc1 · Issue #39589 · JuliaLang/julia · GitHub.

Also see the NEWS entry: Add HISTORY.md entry for change noted in #39589 by sostock · Pull Request #39784 · JuliaLang/julia · GitHub.