update vendor

vendor/github.com/Microsoft/hcsshim/osversion/osversion_windows.go

@@ -15,21 +15,6 @@ type OSVersion struct {
 	Build        uint16
 }
 
-// https://msdn.microsoft.com/en-us/library/windows/desktop/ms724833(v=vs.85).aspx
-type osVersionInfoEx struct {
-	OSVersionInfoSize uint32
-	MajorVersion      uint32
-	MinorVersion      uint32
-	BuildNumber       uint32
-	PlatformID        uint32
-	CSDVersion        [128]uint16
-	ServicePackMajor  uint16
-	ServicePackMinor  uint16
-	SuiteMask         uint16
-	ProductType       byte
-	Reserve           byte
-}
-
 // Get gets the operating system version on Windows.
 // The calling application must be manifested to get the correct version information.
 func Get() OSVersion {

vendor/github.com/Microsoft/hcsshim/osversion/windowsbuilds.go

@@ -24,4 +24,15 @@ const (
 	// V19H1 (version 1903) corresponds to Windows Server 1903 (semi-annual
 	// channel).
 	V19H1 = 18362
+
+	// V19H2 (version 1909) corresponds to Windows Server 1909 (semi-annual
+	// channel).
+	V19H2 = 18363
+
+	// V20H1 (version 2004) corresponds to Windows Server 2004 (semi-annual
+	// channel).
+	V20H1 = 19041
+
+	// V20H2 corresponds to Windows Server 20H2 (semi-annual channel).
+	V20H2 = 19042
 )