Fix cherry-pick related build breaks.

ipn/ipnlocal/local.go: must include net/url.
ipn/ipnlocal/peerapi_test.go: remove tailscale.com/util/must

Signed-off-by: Denton Gentry <dgentry@tailscale.com>

ipn/ipnlocal/local.go

@@ -12,6 +12,7 @@ import (
 	"net"
 	"net/http"
 	"net/netip"
+	"net/url"
 	"os"
 	"os/user"
 	"path/filepath"

ipn/ipnlocal/peerapi_test.go

@@ -25,7 +25,6 @@ import (
 	"tailscale.com/tstest"
 	"tailscale.com/types/logger"
 	"tailscale.com/types/netmap"
-	"tailscale.com/util/must"
 	"tailscale.com/wgengine"
 	"tailscale.com/wgengine/filter"
 )