build: dependencies update

Author: phnx47

src/Prometheus.Client.AspNetCore/Prometheus.Client.AspNetCore.csproj

@@ -33,12 +33,12 @@
     </None>
   </ItemGroup>
   <ItemGroup>
-    <PackageReference Include="Prometheus.Client" Version="4.0.0-dev-1596282179" />
+    <PackageReference Include="Prometheus.Client" Version="4.0.0" />
   </ItemGroup>
   <ItemGroup Condition="'$(TargetFramework)' == 'netcoreapp3.1'">
     <FrameworkReference Include="Microsoft.AspNetCore.App" />
   </ItemGroup>
-  <ItemGroup Condition="'$(TargetFramework)' == 'netstandard2.0' OR '$(TargetFramework)' == 'netcoreapp2.2' OR '$(TargetFramework)' == 'netstandard2.1'">
+  <ItemGroup Condition="'$(TargetFramework)' != 'netcoreapp3.1'">
     <PackageReference Include="Microsoft.AspNetCore.Http.Abstractions" Version="2.2.0" />
   </ItemGroup>
 </Project>