test(twap): edge case tests for geometric twap

[p0mvn]

Background

Currently, most of the test cases for computeGeometricTwap use base values.

To be more confident about correctness, we should add more test cases with hand-picked custom values.

This is an open-ended task so someone having context on the state of geometric twap should be working on this.

Acceptance Criteria

• custom tests added if applicable

[p0mvn]

need to test this function:

osmosis/x/twap/strategy.go

Line 39 in f9c3e06

func (s *geometric) computeTwap(startRecord types.TwapRecord, endRecord types.TwapRecord, quoteAsset string) sdk.Dec {

where arithmeticMeanOfLogPrices is negative. It can happen when sp0 is < 1

[p0mvn]

Revisit this comment while working on this issue: https://github.com/osmosis-labs/osmosis/pull/3809/files#r1053921196

[p0mvn]

We need to test underflows.

Context:

    Do we also need to test min spot price, since this can get underflow? (or is that a future PR?)

Originally posted by @ValarDragon in #3809 (comment)

[p0mvn]

TODO: perform manual CLI test on completion

[p0mvn]

Everything here has been complete but the manual test. Tracking manual test here: #3941