[release] v1.28.1 - GetClientInitializeResponse target app filtering by ID (#225)

### Improvements
- Support `GetClientInitializeResponse` target app filtering using the
target app ID directly rather than the client SDK key





>Included In This Release
>- f89dc82 kenny-statsig
>   - Allow using target app ID directly for GCIR (#223)

Author: kenny-statsig

statsig_metadata.go

@@ -14,7 +14,7 @@ type statsigMetadata struct {
 func getStatsigMetadata() statsigMetadata {
 	return statsigMetadata{
 		SDKType:         "go-sdk",
-		SDKVersion:      "v1.28.0",
+		SDKVersion:      "v1.28.1",
 		LanguageVersion: runtime.Version()[2:],
 		SessionID:       SessionID(),
 	}