fix units/second report

fixes #2

Author: vaind

lib/src/benchmark.dart

@@ -57,12 +57,15 @@ class BenchmarkResult {
     if (units != null) {
       output
         ..labeled('units', units)
-        ..labeled('units/second', runsPerSecond)
+        ..labeled('units/second', unitsPerSecond(units))
         ..labeled('time per unit',
             Printer.formatMicroseconds(microsecondsPerUnit(units)));
     }
   }
 
+  double unitsPerSecond(int units) =>
+      Duration.microsecondsPerSecond / microsecondsPerUnit(units);
+
   double microsecondsPerUnit(int units) =>
       averageRunTime.inMicroseconds / units;
 }

lib/src/printer.dart

@@ -33,7 +33,7 @@ class Printer {
       {String thousandsSeparator = ' ',
       int? decimalPoints,
       String suffix = '   ',
-      int lPadLength = 8}) {
+      int lPadLength = 10}) {
     late String str;
 
     if (number.isInfinite) {