chore: add ping benchmark

Author: nbbeeken

test/benchmarks/mongoBench/suites/singleBench.js

@@ -21,8 +21,22 @@ function makeSingleBench(suite) {
           return this.doc;
         })
     )
+    .benchmark('ping', benchmark =>
+      benchmark
+        .taskSize(0.15) // { ping: 1 } is 15 bytes of BSON x 10,000 iterations
+        .setup(makeClient)
+        .setup(connectClient)
+        .setup(initDb)
+        .task(async function () {
+          for (let i = 0; i < 10000; ++i) {
+            await this.db.command({ ping: 1 });
+          }
+        })
+        .teardown(disconnectClient)
+    )
     .benchmark('runCommand', benchmark =>
       benchmark
+        // { hello: true } is 13 bytes. However the legacy hello was 16 bytes, to preserve history comparison data we leave this value as is.
         .taskSize(0.16)
         .setup(makeClient)
         .setup(connectClient)