Windows: require Windows Server RS5 / ltsc2019 (build 17763) as minimum

Windows Server 2016 (RS1) reached end of support, and Docker Desktop requires
Windows 10 V19H2 (version 1909, build 18363) as a minimum.

This patch makes Windows Server RS5 /  ltsc2019 (build 17763) the minimum version
to run the daemon, and removes some hacks for older versions of Windows.

There is one check remaining that checks for Windows RS3 for a workaround
on older versions, but recent changes in Windows seemed to have regressed
on the same issue, so I kept that code for now to check if we may need that
workaround (again);

085c6a98d5/daemon/graphdriver/windows/windows.go (L319-L341)

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

integration-cli/docker_api_containers_windows_test.go

@@ -12,7 +12,6 @@ import (
 	"testing"
 
 	winio "github.com/Microsoft/go-winio"
-	"github.com/Microsoft/hcsshim/osversion"
 	"github.com/docker/docker/api/types"
 	"github.com/docker/docker/api/types/container"
 	"github.com/docker/docker/api/types/mount"
@@ -22,8 +21,6 @@ import (
 )
 
 func (s *DockerSuite) TestContainersAPICreateMountsBindNamedPipe(c *testing.T) {
-	testRequires(c, testEnv.IsLocalDaemon, DaemonIsWindowsAtLeastBuild(osversion.RS3)) // Named pipe support was added in RS3
-
 	// Create a host pipe to map into the container
 	hostPipeName := fmt.Sprintf(`\\.\pipe\docker-cli-test-pipe-%x`, rand.Uint64())
 	pc := &winio.PipeConfig{