Twap test structure

[anxolin]

This PR just restructures the tests.

In my opinion, tests should assert one thing. This will make it easier to understand the scope, maintain, and know exactly what is wrong when tests start to fail.

For this reason, I reorganized the tests (in anticipation to the fact I want to create a new PR with new tests)

Conditional Order

Twap

[github-actions]

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[coveralls]

coverage: 72.617%. remained the same when pulling 0831e0d on twap-test-structure into 3a61922 on main.

[anxolin]

Addressed the comments and low risk PR (also test pass)

I will merge to not waterfall too much