FIX-#7143: Constructing a DataFrame from a Modin Series with tuple name should produce MultiIndex columns

[noloerino]

What do these changes do?

Fixes a bug where creating a DF from a Series with tuple name did not give the DF a MultiIndex object for its columns property. This PR sets the underlying query compiler's object to be a MultiIndex when the Series is created.

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• passes flake8 modin/ asv_bench/benchmarks scripts/doc_checker.py
• passes black --check modin/ asv_bench/benchmarks scripts/doc_checker.py
• signed commit with git commit -s
• Resolves BUG: Constructing a DataFrame from a Modin Series with tuple name should produce MultiIndex columns #7143
• tests added and passing
• module layout described at docs/development/architecture.rst is up-to-date

[anmyachev]

Hi @noloerino! Overall it looks good! However, it may be more reliable to check the entire objects themselves, and not just the index (for example, using eval_general). What do you think?

[noloerino]

Sounds good. I didn't add eval_general since this is testing the DF constructor and not any methods on top of it, but I changed it to use df_equals instead.

[anmyachev]

Thanks @noloerino!

[anmyachev]

@noloerino please also sign your commits with git commit -s.

[sfc-gh-joshi]

Should be fixed now, thanks.