test: fix test-benchmark-zlib

The addition of brotli to zlib benchmarks means that test-benchmark-zlib
needs to be modified. This is that modification.

PR-URL: nodejs#25365
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>

test/benchmark/test-benchmark-zlib.js

@@ -6,6 +6,7 @@ const runBenchmark = require('../common/benchmark');
 
 runBenchmark('zlib',
              [
+               'algorithm=brotli',
                'method=deflate',
                'n=1',
                'options=true',