chore(deps): update all non-major dependencies to 0.15.8 (#22)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

tests/ZaString.Benchmarks/ZaString.Benchmarks.csproj

@@ -13,8 +13,8 @@
         <IsPackable>false</IsPackable>
     </PropertyGroup>
     <ItemGroup>
-        <PackageReference Include="BenchmarkDotNet" Version="0.15.7" />
-        <PackageReference Include="BenchmarkDotNet.Diagnostics.Windows" Version="0.15.7" />
+        <PackageReference Include="BenchmarkDotNet" Version="0.15.8" />
+        <PackageReference Include="BenchmarkDotNet.Diagnostics.Windows" Version="0.15.8" />
     </ItemGroup>
     <ItemGroup>
         <ProjectReference Include="..\..\src\ZaString\ZaString.csproj"/>