add missing imports

Author: rnro

Sources/SWIM/SWIMInstance.swift

@@ -13,6 +13,7 @@
 //===----------------------------------------------------------------------===//
 
 import ClusterMembership
+import CoreMetrics
 import Logging
 
 import struct Dispatch.DispatchTime

Sources/SWIMNIOExample/SWIMNIOHandler.swift

@@ -13,10 +13,16 @@
 //===----------------------------------------------------------------------===//
 
 import ClusterMembership
+import CoreMetrics
 import Logging
 import NIO
 import NIOFoundationCompat
 import SWIM
+#if canImport(FoundationEssentials)
+import FoundationEssentials
+#else
+import Foundation
+#endif
 
 import struct Dispatch.DispatchTime
 

Sources/SWIMNIOExample/SWIMNIOShell.swift

@@ -14,6 +14,7 @@
 
 import ClusterMembership
 import Logging
+import Metrics
 import NIO
 import SWIM
 

Tests/SWIMNIOExampleTests/SWIMNIOClusteredTests.swift

@@ -16,6 +16,7 @@ import ClusterMembership
 import Logging
 import NIO
 import SWIM
+import SWIMTestKit
 import XCTest
 
 @testable import SWIMNIOExample