title: The author primary signature's timestamp found a chain building issue: UntrustedRoot: self signed certificate in certificate chain
body: <p>While doing a docker build on my .NET Core project, I got the following error on all my NuGets:</p>
  <blockquote>
  <p>80.19 /app/GradingTool.Tests/GradingTool.Tests.csproj : error NU3028: Package 'Microsoft.EntityFrameworkCore 5.0.0' from source 'https://api.nuget.org/v3/index.json': The author primary signature's timestamp found a chain building issue: UntrustedRoot: self signed certificate in certificate chain [/app/GradingTool.sln]</p>
  <p>#12 80.20 /app/GradingTool.Tests/GradingTool.Tests.csproj : error NU3037: Package 'Microsoft.EntityFrameworkCore 5.0.0' from source 'https://api.nuget.org/v3/index.json': The author primary signature validity period has expired. [/app/GradingTool.sln]</p>
  <p>#12 80.20 /app/GradingTool.Tests/GradingTool.Tests.csproj : error NU3028: Package 'Microsoft.EntityFrameworkCore 5.0.0' from source 'https://api.nuget.org/v3/index.json': The repository countersignature's timestamp found a chain building issue: UntrustedRoot: self signed certificate in certificate chain [/app/GradingTool.sln]</p>
  </blockquote>
  <p>I never had this error before,
  Can someone help me figure out what the problem is?</p>
  <p>Dockerfile:</p>
  <pre><code>FROM mcr.microsoft.com/dotnet/sdk:latest AS build-env
  WORKDIR /app
  RUN apt-get update -yq \
      &amp;&amp; apt-get install curl gnupg -yq \
      &amp;&amp; curl -sL https://deb.nodesource.com/setup_10.x | bash \
      &amp;&amp; apt-get install nodejs -yq
  # Copy csproj and restore as distinct layers
  COPY . ./
  RUN dotnet restore
  RUN dotnet publish -c Release -o out
  
  # Build runtime image
  FROM mcr.microsoft.com/dotnet/aspnet:latest
  RUN apt-get update \
      &amp;&amp; apt-get install -y --no-install-recommends libgdiplus libc6-dev \
      &amp;&amp; apt-get clean \
      &amp;&amp; rm -rf /var/lib/apt/lists/*
  WORKDIR /app
  COPY --from=build-env /app/out .
  ENV ASPNETCORE_URLS=&quot;http://+:4200&quot;
  ENV ASPNETCORE_ENVIRONMENT=&quot;Production&quot;
  ENV GOOGLE_APPLICATION_CREDENTIALS=&quot;Credentials/SchoolTools-e9f260bdf56e.json&quot;
  ENV VIRTUAL_HOST=&quot;eva.schooltools.lu,www.eva.schooltools.lu,schooltools.lu,www.schooltools.lu&quot;
  ENV LETSENCRYPT_HOST=&quot;eva.schooltools.lu,www.eva.schooltools.lu,schooltools.lu,www.schooltools.lu&quot;
  ENV LETSENCRYPT_EMAIL=&quot;wilson.silva@edutec.lu&quot;
  EXPOSE 4200
  ENTRYPOINT [&quot;dotnet&quot;, &quot;GradingTool.dll&quot;]
  </code></pre>