test_runner: fix duration_ms to be milliseconds

PR-URL: nodejs#44450
Backport-PR-URL: nodejs#44873
Reviewed-By: Benjamin Gruenbaum <[email protected]>
Reviewed-By: Antoine du Hamel <[email protected]>
Reviewed-By: Franziska Hinkelmann <[email protected]>
Reviewed-By: Rich Trott <[email protected]>
Reviewed-By: Minwoo Jung <[email protected]>

Author: MoLow

lib/internal/test_runner/test.js

@@ -619,8 +619,8 @@ class Test extends AsyncResource {
   }
 
   #duration() {
-    // Duration is recorded in BigInt nanoseconds. Convert to seconds.
-    return Number(this.endTime - this.startTime) / 1_000_000_000;
+    // Duration is recorded in BigInt nanoseconds. Convert to milliseconds.
+    return Number(this.endTime - this.startTime) / 1_000_000;
   }
 
   report() {