Silence ZDNS status updates with make benchmark

[phillip-stephens]

After adding the per-second logs to ZDNS, the benchmark doesn't print cleanly. This is a simple fix for that.

Before change:

$ make benchmark
go generate ./...
go build -o zdns
cd ./benchmark && go run main.go stats.go
Benchmarking ZDNS, Resolving 7000 domains...   5% |█                        | (369/7000, 370 it/s) [0s:17s]
StdErr: 00h:00m:01s; 393 names scanned; 392.79 names/sec; 99.7% success rate; NOERROR: 391, NXDOMAIN: 1, REFUSED: 1
Benchmarking ZDNS, Resolving 7000 domains...  11% |██                       | (832/7000, 429 it/s) [1s:14s]
StdErr: 00h:00m:02s; 851 names scanned; 425.49 names/sec; 99.6% success rate; NOERROR: 844, NXDOMAIN: 4, REFUSED: 3
Benchmarking ZDNS, Resolving 7000 domains...  17% |████                    | (1241/7000, 434 it/s) [2s:13s]
StdErr: 00h:00m:03s; 1255 names scanned; 418.32 names/sec; 99.6% success rate; NOERROR: 1243, NXDOMAIN: 7, REFUSED: 5
Benchmarking ZDNS, Resolving 7000 domains...  21% |█████                   | (1506/7000, 418 it/s) [3s:13s]^Csignal: interrupt
make: *** [makefile:39: benchmark] Interrupt

After change:

$ make benchmark
go generate ./...
go build -o zdns
cd ./benchmark && go run main.go stats.go
Benchmarking ZDNS, Resolving 7000 domains...  17% |████                    | (1223/7000, 443 it/s) [2s:13s]^Csignal: interrupt
make: *** [makefile:39: benchmark] Interrupt