Add OS platform checks to deterministic msbuild tests

Modified `Msbuild` and `Msbuild_SourceLink` test methods to skip execution on Linux

Author: Bertk

test/coverlet.integration.tests/DeterministicBuild.cs

@@ -5,6 +5,7 @@
 using System.IO;
 using System.Linq;
 using System.Reflection;
+using System.Runtime.InteropServices;
 using System.Xml.Linq;
 using Coverlet.Core;
 using Coverlet.Tests.Utils;
@@ -87,6 +88,7 @@ private protected void AssertCoverage(string standardOutput = "", bool checkDete
     [Fact]
     public void Msbuild()
     {
+      Assert.SkipWhen(RuntimeInformation.IsOSPlatform(OSPlatform.Linux), "Test requires Windows");
       string testResultPath = Path.Join(_testResultsPath, $"{TestContext.Current.TestClass?.TestClassName}.{TestContext.Current.TestMethod?.MethodName}");
       string logFilename = $"{TestContext.Current.TestClass?.TestClassName}.{TestContext.Current.TestMethod?.MethodName}.binlog";
       CreateDeterministicTestPropsFile();
@@ -130,6 +132,7 @@ public void Msbuild()
     [Fact]
     public void Msbuild_SourceLink()
     {
+      Assert.SkipWhen(RuntimeInformation.IsOSPlatform(OSPlatform.Linux), "Test requires Windows");
       string testResultPath = Path.Join(_testResultsPath, $"{TestContext.Current.TestClass?.TestClassName}.{TestContext.Current.TestMethod?.MethodName}");
       string logFilename = $"{TestContext.Current.TestClass?.TestClassName}.{TestContext.Current.TestMethod?.MethodName}.binlog";
       CreateDeterministicTestPropsFile();