CBG-4289 fix import CV value for HLV code

[torcolvin]

Created new tests to cover import cases https://docs.google.com/document/d/19mC9-TptN7ynuF5XR9TQ_MckHWsSrjUfI2p71G_DD1U/edit#heading=h.xzdilbaiwy25

The specific bugs initially noticed were around _vv.ver getting updated to newVVEntry.Value = expandMacroCASValueUint64 which was never correct on import. Additional logic was expanded to cover all tests.

For ease of reading this code, the existing tests were ported to a parameterized test first with the buggy logic in place, you can read the commit separately.

Some tests are disabled are set to fix at a future time https://jira.issues.couchbase.com/browse/CBG-4292. Before working on that ticket, https://jira.issues.couchbase.com/browse/CBG-4291 should be fixed on main and rebased onto anemone.

Code is also tested with live XDCR.

Also removes ImportCAS as part of CBG-4285.

Pre-review checklist

• Removed debug logging (fmt.Print, log.Print, ...)
• Logging sensitive data? Make sure it's tagged (e.g. base.UD(docID), base.MD(dbName))
• Updated relevant information in the API specifications (such as endpoint descriptions, schemas, ...) in docs/api

Integration Tests

• GSI=true,xattrs=true https://jenkins.sgwdev.com/job/SyncGateway-Integration/2746/

[adamcfraser]

Functionally looks ok, some suggestions for clarity on the comments/conditions.

[adamcfraser]

I think the description as you've got it muddies the rationale behind the decision making here (simply that we want to update the HLV only if the current document cas isn't already accounted for in the HLV + mou).

Suggested change

	// Update HLV if:
	// Do not update HLV if the current document version (cas) is already included in the existing HLV,
	// as either:
	// 1. _vv.cvCAS == document.cas (current mutation is already present as cv), or
	// 2. _mou.cas == document.cas (current mutation is already present as cv, and was imported on a different cluster)

[adamcfraser]

If this can be rewritten to match the comment suggestion I think that would be more readable. Even something like this maybe:

cvCASMatch := hasHLV && d.HLV.CurrentVersionCAS == d.Cas
mouMatch := previousMou != nil && base.HexCasToUint64(previousMou.CAS) == d.Cas)
if !cvCASMatch && !mouMatch {