Wait for pending changes after doc updates

[gregns1]

CBG-0000

• Add wait for pending changes for reconcile rev tree tests

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

Dependencies (if applicable)

• Link upstream PRs
• Update Go module dependencies when merged

Integration Tests

• GSI=true,xattrs=true https://jenkins.sgwdev.com/job/SyncGatewayIntegration/0000/

[Copilot]

Pull Request Overview

This PR adds synchronization improvements to replicator revision tree tests by introducing wait calls for pending changes after document updates. The changes ensure that document updates are fully processed before continuing with replication operations, which should improve test reliability.

Key changes:

• Added WaitForPendingChanges() calls after document updates in replicator tests
• Enhanced logging by adding base.KeyHTTPResp to test setup