FIX use canImport instead of swift(>=5.1) && os(Linux)

Author: Andrea-Scuderi

Examples/HTTPSRequest/Sources/HTTPSRequest/main.swift

@@ -14,7 +14,7 @@
 
 import AsyncHTTPClient
 import Foundation
-#if swift(>=5.1) && os(Linux)
+#if canImport(FoundationNetworking)
     import FoundationNetworking
 #endif
 import LambdaSwiftSprinter

Examples/HelloWorld/Sources/HelloWorld/main.swift

@@ -13,7 +13,7 @@
 //    limitations under the License.
 
 import Foundation
-#if swift(>=5.1) && os(Linux)
+#if canImport(FoundationNetworking)
     import FoundationNetworking
 #endif
 import LambdaSwiftSprinter

Examples/S3Test/Sources/S3Test/main.swift

@@ -13,7 +13,7 @@
 //    limitations under the License.
 
 import Foundation
-#if swift(>=5.1) && os(Linux)
+#if canImport(FoundationNetworking)
     import FoundationNetworking
 #endif
 import LambdaSwiftSprinter