test: fix long-running http benchmarks

PR-URL: https://github.com/nodejs/node/pull/20125
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Rich Trott <rtrott@gmail.com>

benchmark/http/cluster.js

@@ -26,7 +26,7 @@ function main({ type, len, c }) {
     if (workers < 2)
       return;
 
-    setTimeout(function() {
+    setImmediate(function() {
       const path = `/${type}/${len}`;
 
       bench.http({
@@ -36,6 +36,6 @@ function main({ type, len, c }) {
         w1.destroy();
         w2.destroy();
       });
-    }, 100);
+    });
   });
 }

test/sequential/test-benchmark-http.js

@@ -18,12 +18,14 @@ runBenchmark('http',
                'chunkedEnc=true',
                'chunks=0',
                'dur=0.1',
+               'input=keep-alive',
                'key=""',
                'len=1',
                'method=write',
                'n=1',
                'res=normal',
-               'type=asc'
+               'type=asc',
+               'value=X-Powered-By'
              ],
              {
                NODEJS_BENCHMARK_ZERO_ALLOWED: 1,