Swift 5.1 support

Use stdlib Result instead of TAsyncResult

Fix: deprecations for `withUnsafeBytes`

Bump CI job Xcode version

Hash (into)

Co-authored-by: Sophie Lambrakis <SLambrakis@users.noreply.github.com>
Co-authored-by: Alexander Edge <alex@alexedge.co.uk>
diff --git a/lib/swift/Sources/TSocketServer.swift b/lib/swift/Sources/TSocketServer.swift
index a3c6389..6cfb5a1 100644
--- a/lib/swift/Sources/TSocketServer.swift
+++ b/lib/swift/Sources/TSocketServer.swift
@@ -82,7 +82,7 @@
       let address = Data(bytes: ptr, count: MemoryLayout<sockaddr_in>.size)
 
       let cfaddr = address.withUnsafeBytes {
-        CFDataCreateWithBytesNoCopy(kCFAllocatorDefault, $0, address.count, nil)
+        CFDataCreateWithBytesNoCopy(kCFAllocatorDefault, $0.bindMemory(to: UInt8.self).baseAddress!, address.count, nil)
       }
       if CFSocketSetAddress(sock, cfaddr) != CFSocketError.success { //kCFSocketSuccess {
         CFSocketInvalidate(sock)