Fix Docker core dumps when removing network with special characters (#21401).

This fix tries to fix Docker core dumps when removing network with special
characters. The issue is from the fact that when docker client tries to
pass the command to API, the networkID is not escaped in case of special
characters. This also means other commands (not just `docker network rm`)
may face the same issue (e.g., `docker network connect`).

This fix adds the URL path escape to properly handle it. In addition, an
integration test for network create and delete is added to cover the cases
in #21401.

This fix fixes #21401.

Signed-off-by: Yong Tang <yong.tang.github@outlook.com>
(cherry picked from commit f8dc5562d0)
Signed-off-by: David Calavera <david.calavera@gmail.com>
(cherry picked from commit f154227608)

integration-cli/docker_cli_network_unix_test.go

@@ -1452,3 +1452,16 @@ func (s *DockerSuite) TestDockerNetworkInternalMode(c *check.C) {
 	_, _, err = dockerCmdWithError("exec", "second", "ping", "-c", "1", "first")
 	c.Assert(err, check.IsNil)
 }
+
+// Test for #21401
+func (s *DockerNetworkSuite) TestDockerNetworkCreateDeleteSpecialCharacters(c *check.C) {
+	dockerCmd(c, "network", "create", "test@#$")
+	assertNwIsAvailable(c, "test@#$")
+	dockerCmd(c, "network", "rm", "test@#$")
+	assertNwNotAvailable(c, "test@#$")
+
+	dockerCmd(c, "network", "create", "kiwl$%^")
+	assertNwIsAvailable(c, "kiwl$%^")
+	dockerCmd(c, "network", "rm", "kiwl$%^")
+	assertNwNotAvailable(c, "kiwl$%^")
+}