[Chaitana's Colossal Coaster] / [List Methods] Remove unused variable assignment in list_methods_test.py

[leonqadirie]

Semantically covered by the prior test, so the variable is not needed.

Consequentially, the assigned variable is not used in this test. To not generate warnings, I suggest to not assign the return value at all.

[github-actions]

This PR touches files which potentially affect the outcome of the tests of an exercise. This will cause all students' solutions to affected exercises to be re-tested.

If this PR does not affect the result of the test (or, for example, adds an edge case that is not worth rerunning all tests for), please add the following to the merge-commit message which will stops student's tests from re-running. Please copy-paste to avoid typos.

[no important files changed]

For more information, refer to the documentation. If you are unsure whether to add the message or not, please ping @exercism/maintainers-admin in a comment. Thank you!

[github-actions]

Hello. Thanks for opening a PR on Exercism 🙂

We ask that all changes to Exercism are discussed on our Community Forum before being opened on GitHub. To enforce this, we automatically close all PRs that are submitted. That doesn't mean your PR is rejected but that we want the initial discussion about it to happen on our forum where a wide range of key contributors across the Exercism ecosystem can weigh in.

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[leonqadirie]

Forum discussion here

[kotp]

Supercedes:

• [Chaitana's Colossal Coaster] / [List Methods]: Change instructions to not return a copy #3818
• [Chaitana's Colossal Coaster] / [List Methods]: Change instructions to not return a copy #3819

[kotp]

Also forum discussion here.

[leonqadirie]

Supercedes:

• [Chaitana's Colossal Coaster] / [List Methods]: Change instructions to not return a copy #3818
• [Chaitana's Colossal Coaster] / [List Methods]: Change instructions to not return a copy #3819

Thanks! But actually, this one is a separate issue. The forum discussion in turn is correctly linked.
I will add the supersession message to #3819.

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If this PR does not affect the result of the test (or, for example, adds an edge case that is not worth rerunning all tests for), please add the following to the merge-commit message which will stops student's tests from re-running. Please copy-paste to avoid typos.

[no important files changed]

Will do once this one is agreed to make sense on the forum.