Update split SDK to 6.0.2 to fix sync bug (#17060)

* Update split SDK to 6.0.2 to fix sync bug

* Vendor and tidy

vendor/github.com/splitio/go-split-commons/v3/synchronizer/interface.go

@@ -0,0 +1,13 @@
+package synchronizer
+
+// Synchronizer interface for syncing data to and from splits servers
+type Synchronizer interface {
+	SyncAll(requestNoCache bool) error
+	SynchronizeSplits(till *int64, requestNoCache bool) error
+	LocalKill(splitName string, defaultTreatment string, changeNumber int64)
+	SynchronizeSegment(segmentName string, till *int64, requestNoCache bool) error
+	StartPeriodicFetching()
+	StopPeriodicFetching()
+	StartPeriodicDataRecording()
+	StopPeriodicDataRecording()
+}