Update Program.cs (#708)

Added benchmarks for UnitSystem methods (UnitSystem.SI)

Author: lipchev

UnitsNet.Benchmark/Program.cs

@@ -13,6 +13,9 @@ public class UnitsNetBenchmarks
         [Benchmark]
         public Length Constructor() => new Length(3.0, LengthUnit.Meter);
 
+        [Benchmark]
+        public Length Constructor_SI() => new Length(3.0, UnitSystem.SI);
+
         [Benchmark]
         public Length FromMethod() => Length.FromMeters(3.0);
 
@@ -22,9 +25,15 @@ public class UnitsNetBenchmarks
         [Benchmark]
         public double As() => length.As(LengthUnit.Centimeter);
 
+        [Benchmark]
+        public double As_SI() => length.As(UnitSystem.SI);
+
         [Benchmark]
         public Length ToUnit() => length.ToUnit(LengthUnit.Centimeter);
 
+        [Benchmark]
+        public Length ToUnit_SI() => length.ToUnit(UnitSystem.SI);
+
         [Benchmark]
         public string ToStringTest() => length.ToString();
 
@@ -43,6 +52,9 @@ public class UnitsNetBenchmarks
         [Benchmark]
         public double IQuantity_As() => lengthIQuantity.As(LengthUnit.Centimeter);
 
+        [Benchmark]
+        public double IQuantity_As_SI() => lengthIQuantity.As(UnitSystem.SI);
+
         [Benchmark]
         public IQuantity IQuantity_ToUnit() => lengthIQuantity.ToUnit(LengthUnit.Centimeter);