Rename to clarify snowplow-specific feature

Author: colmsnowplow

pkg/transform/gtmss_preview.go renamed to pkg/transform/snowplow_gtmss_preview.go

@@ -43,7 +43,7 @@ func gtmssPreviewConfigFunction() (TransformationFunction, error) {
 
 // GTMSSPreviewConfigPair is the configuration pair for the gtmss preview transformation
 var GTMSSPreviewConfigPair = config.ConfigurationPair{
-	Name:   "gtmssPreview",
+	Name:   "spGtmssPreview",
 	Handle: gtmssPreviewAdapterGenerator(gtmssPreviewConfigFunction),
 }