sandbox: support vsock connection to task api

Signed-off-by: Abel Feng <fshb1988@gmail.com>

vendor/github.com/mdlayher/socket/doc.go

@@ -0,0 +1,13 @@
+// Package socket provides a low-level network connection type which integrates
+// with Go's runtime network poller to provide asynchronous I/O and deadline
+// support.
+//
+// This package focuses on UNIX-like operating systems which make use of BSD
+// sockets system call APIs. It is meant to be used as a foundation for the
+// creation of operating system-specific socket packages, for socket families
+// such as Linux's AF_NETLINK, AF_PACKET, or AF_VSOCK. This package should not
+// be used directly in end user applications.
+//
+// Any use of package socket should be guarded by build tags, as one would also
+// use when importing the syscall or golang.org/x/sys packages.
+package socket