Added deserialize benchmarks

Author: Martin Boje Carpentier

src/GeoJSON.Text.Test.Benchmark/Deserialize/DeserializeFeatureCollectionLinestring.cs

@@ -0,0 +1,32 @@
+using BenchmarkDotNet.Attributes;
+using BenchmarkDotNet.Jobs;
+
+namespace GeoJSON.Text.Test.Benchmark.Deserialize
+{
+    [SimpleJob(RuntimeMoniker.Net60, baseline: true)]
+    [SimpleJob(RuntimeMoniker.Net50)]
+    [SimpleJob(RuntimeMoniker.NetCoreApp31)]
+    [MemoryDiagnoser]
+    public class DeserializeFeatureCollectionLinestring
+    {
+        string fileContents = "";
+
+        [Params(1000, 10000, 100000)]
+        public int N;
+
+        [GlobalSetup]
+        public void Setup()
+        {
+            fileContents = JsonEmbeddedFileReader.GetExpectedJson($"DeserializeFeatureCollectionLinestring_{N}");
+        }
+
+#pragma warning disable CS8603 // Possible null reference return.
+        [Benchmark]
+        public Net.Feature.FeatureCollection DeserializeNewtonsoft() => Newtonsoft.Json.JsonConvert.DeserializeObject<Net.Feature.FeatureCollection>(fileContents);
+
+
+        [Benchmark]
+        public Text.Feature.FeatureCollection DeserializeSystemTextJson() => System.Text.Json.JsonSerializer.Deserialize<Text.Feature.FeatureCollection>(fileContents);
+#pragma warning restore CS8603 // Possible null reference return.
+    }
+}