Change readme

Author: ktoso

Package.swift

@@ -50,6 +50,13 @@ let package = Package(
                 .target(name: "Tracing"),
             ]
         ),
+        .testTarget(
+            name: "TracingLegacyTests",
+            dependencies: [
+                .target(name: "Tracing"),
+                .product(name: "InstrumentationBaggage", package: "swift-service-context"),
+            ]
+        ),
 
         // ==== --------------------------------------------------------------------------------------------------------
         // MARK: Performance / Benchmarks