title: Atleast one invalid signature was encountered
body: <p>I am trying to build and deploy microservices images to a single-node Kubernetes cluster running on my development machine using minikube. I am using the cloud-native microservices demo application Online Boutique by Google to understand the use of technologies like Kubernetes, Istio etc. </p>
  
  <p>Link to github repo: <a href="https://github.com/GoogleCloudPlatform/microservices-demo" rel="noreferrer">microservices-demo</a></p>
  
  <p>While following the installation process, and on running command <code>skaffold run</code> to build and deploy my application, I get some errors:</p>
  
  <pre><code>Step 10/11 : RUN apt-get -qq update     &amp;&amp; apt-get install -y --no-install-recommends         curl
   ---&gt; Running in 43d61232617c
  W: GPG error: http://deb.debian.org/debian buster InRelease: At least one invalid signature was encountered.
  E: The repository 'http://deb.debian.org/debian buster InRelease' is not signed.
  W: GPG error: http://deb.debian.org/debian buster-updates InRelease: At least one invalid signature was encountered.
  E: The repository 'http://deb.debian.org/debian buster-updates InRelease' is not signed.
  W: GPG error: http://security.debian.org/debian-security buster/updates InRelease: At least one invalid signature was encountered.
  E: The repository 'http://security.debian.org/debian-security buster/updates InRelease' is not signed.
  failed to build: couldn't build "loadgenerator": unable to stream build output: The command '/bin/sh -c apt-get -qq update     &amp;&amp; apt-get install -y --no-install-recommends         curl' returned a non-zero code: 100
  </code></pre>
  
  <p>I receive these errors when trying to build loadgenerator.
  How can I resolve this issue? </p>