fix build warnings

Author: arturcic

src/Directory.Build.props

@@ -18,7 +18,7 @@
         <RepositoryUrl>https://github.com/GitTools/GitVersion</RepositoryUrl>
         <RepositoryType>git</RepositoryType>
 
-        <NoWarn>$(NoWarn);1591,8618,SYSLIB10;EnableGenerateDocumentationFile</NoWarn>
+        <NoWarn>$(NoWarn);NU1701;1591,8618,SYSLIB10;EnableGenerateDocumentationFile</NoWarn>
         <WarningsAsErrors>$(WarningsAsErrors);RS0016;RS0017;RS0022;RS0024;RS0025;RS0026;RS0027</WarningsAsErrors>
 
         <DebugType>embedded</DebugType>

src/Directory.Packages.props

@@ -8,6 +8,7 @@
     <PackageVersion Include="JunitXml.TestLogger" Version="3.1.12" />
     <PackageVersion Include="LibGit2Sharp" Version="0.29.0" />
     <PackageVersion Include="MSBuild.ProjectCreation" Version="11.0.1" />
+    <PackageVersion Include="Microsoft.Bcl.AsyncInterfaces" Version="8.0.0" />
     <PackageVersion Include="Microsoft.Build" Version="17.9.5" />
     <PackageVersion Include="Microsoft.Build.Utilities.Core" Version="17.9.5" />
     <PackageVersion Include="Microsoft.CodeAnalysis.CSharp" Version="4.8.0" />

src/GitVersion.MsBuild.Tests/GitVersion.MsBuild.Tests.csproj

@@ -4,6 +4,7 @@
         <PackageReference Include="MSBuild.ProjectCreation" />
         <PackageReference Include="Buildalyzer" />
         <PackageReference Include="LibGit2Sharp" />
+        <PackageReference Include="Microsoft.Bcl.AsyncInterfaces" />
         <PackageReference Include="Microsoft.Build" />
         <PackageReference Include="Microsoft.Build.Utilities.Core" />
     </ItemGroup>