Changed how we get the docker port

Signed-off-by: David Gannon <19214156+dgannon991@users.noreply.github.com>

Author: dgannon991

e2e/helper_test.go

@@ -38,5 +38,6 @@ func (c *Container) Stop(t *testing.T) {
 // GetAddress returns the host:port this container listens on
 func (c *Container) GetAddress(t *testing.T) string {
 	result := icmd.RunCommand("docker", "port", c.container, strconv.Itoa(c.privatePort)).Assert(t, icmd.Success)
-	return fmt.Sprintf("127.0.0.1:%v", strings.Trim(strings.Split(result.Stdout(), ":")[1], " \r\n"))
+	port := strings.Split(strings.Split(result.Stdout(), ":")[1], "\n")[0]
+	return fmt.Sprintf("127.0.0.1:%v", strings.Trim(port, " \r\n"))
 }