Bump Fake.IO.FileSystem and FSharp.Core (#45)

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

build.fsproj

@@ -11,7 +11,7 @@
       <PackageReference Include="Fake.Core.Target" Version="6.0.0" />
       <PackageReference Include="Fake.DotNet.Cli" Version="6.0.0" />
       <PackageReference Include="Fake.DotNet.MSBuild" Version="6.0.0" />
-      <PackageReference Include="Fake.IO.FileSystem" Version="6.0.0" />
+      <PackageReference Include="Fake.IO.FileSystem" Version="6.1.3" />
       <PackageReference Include="MSBuild.StructuredLogger" Version="2.2.441" />
       <PackageReference Include="NuGet.Common" Version="6.13.2" />
       <PackageReference Include="NuGet.Packaging" Version="6.9.1" />