testing: TCPServer was only used in secondary_test.go (#3186)

TCPServer was only used in secondary_test.go and even there it wasn't
needed. Remove the file.

Signed-off-by: Miek Gieben <miek@miek.nl>

plugin/test/server.go

@@ -1,52 +0,0 @@
-package test
-
-import (
-	"net"
-	"sync"
-	"time"
-
-	"github.com/miekg/dns"
-)
-
-// TCPServer starts a DNS server with a TCP listener on laddr.
-func TCPServer(laddr string) (*dns.Server, string, error) {
-	l, err := net.Listen("tcp", laddr)
-	if err != nil {
-		return nil, "", err
-	}
-
-	server := &dns.Server{Listener: l, ReadTimeout: time.Hour, WriteTimeout: time.Hour}
-
-	waitLock := sync.Mutex{}
-	waitLock.Lock()
-	server.NotifyStartedFunc = func() { waitLock.Unlock() }
-
-	go func() {
-		server.ActivateAndServe()
-		l.Close()
-	}()
-
-	waitLock.Lock()
-	return server, l.Addr().String(), nil
-}
-
-// UDPServer starts a DNS server with an UDP listener on laddr.
-func UDPServer(laddr string) (*dns.Server, string, error) {
-	pc, err := net.ListenPacket("udp", laddr)
-	if err != nil {
-		return nil, "", err
-	}
-	server := &dns.Server{PacketConn: pc, ReadTimeout: time.Hour, WriteTimeout: time.Hour}
-
-	waitLock := sync.Mutex{}
-	waitLock.Lock()
-	server.NotifyStartedFunc = func() { waitLock.Unlock() }
-
-	go func() {
-		server.ActivateAndServe()
-		pc.Close()
-	}()
-
-	waitLock.Lock()
-	return server, pc.LocalAddr().String(), nil
-}