feat(twap): historic pruning

[p0mvn]

Closes: #2197

What is the purpose of the change

Adds TWAP historic pruning and tests.

Brief Changelog

• [x] implement pruning in pruneRecordsBeforeTime
• [x] implement getters for all records and unit test them (helpers_test.go)
• [x] use getters to test the pruning logic
• [x] reuse denom constants in tests
• [x] Create follow-up issue for AfterEpochEnd tests: https://github.com/osmosis-labs/osmosis/issues/2372
• [x] Create follow-up issue for setting pruning-keep period via parameter: https://github.com/osmosis-labs/osmosis/issues/2371

Testing and Verifying

This change added tests and can be verified as follows:

• TestGetAllHistoricalPoolIndexedTWAPs
• TestGetAllHistoricalTimeIndexedTWAPs
• TestPruneRecordsBeforeTime

Documentation and Release Note

• Does this pull request introduce a new feature or user-facing behavior changes? yes
• Is a relevant changelog entry added to the Unreleased section in CHANGELOG.md? no
• How is the feature or change documented? not applicable

[ValarDragon]

We should remove

//nolint:unused,deadcode

right above

//nolint:unused,deadcode
func (k Keeper) deleteHistoricalRecord(ctx sdk.Context, twap types.TwapRecord) {

[p0mvn]

Thanks for the reviews everyone!