Fix build problems on Linux

The difference in casing between the file and the
reference in the project file produced errors building
on Azure DevOps on an Ubuntu system.

Author: KevinSchiener

angular/AbpCompanyName.AbpProjectName.AngularUI.csproj

@@ -14,7 +14,7 @@
 
   <ItemGroup>
     <Compile Remove="dist" />
-    <None Include="App.config" />
+    <None Include="app.config" />
     <None Update="wwwroot\**\*;web.config">
       <CopyToPublishDirectory>PreserveNewest</CopyToPublishDirectory>
     </None>