feat(deps): update dotnet monorepo to v8 (major) (#119)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>
Co-authored-by: Michael Kriese <michael.kriese@visualon.de>

Author: renovate[bot]

EPPlus/EPPlus.csproj

@@ -55,15 +55,15 @@
   </ItemGroup>
 
   <ItemGroup Condition="'$(TargetFramework)' == 'net6.0' or '$(TargetFramework)' == 'net8.0'">
-    <PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="7.0.0" />
+    <PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="8.0.0" />
     <PackageReference Include="System.ComponentModel.TypeConverter" Version="4.3.0" />
     <PackageReference Include="System.Data.Common" Version="4.3.0" />
     <PackageReference Include="System.Drawing.Common" Version="4.7.3" />
     <PackageReference Include="System.Reflection" Version="4.3.0" />
     <PackageReference Include="System.Security.Claims" Version="4.3.0" />
-    <PackageReference Include="System.Security.Cryptography.Pkcs" Version="7.0.3" />
+    <PackageReference Include="System.Security.Cryptography.Pkcs" Version="8.0.0" />
     <PackageReference Include="System.Security.Cryptography.X509Certificates" Version="4.3.2" />
-    <PackageReference Include="System.Text.Encoding.CodePages" Version="7.0.0" />
+    <PackageReference Include="System.Text.Encoding.CodePages" Version="8.0.0" />
     <PackageReference Include="System.Xml.XmlDocument" Version="4.3.0" />
     <PackageReference Include="System.Xml.XPath.XmlDocument" Version="4.3.0" />
   </ItemGroup>