Update main.yml

Author: lmangani

.github/workflows/main.yml

@@ -81,7 +81,7 @@ jobs:
         if: ${{ matrix.name == 'linux' && matrix.arch == 'arm64' }}
         run: |
           docker run --rm -v $(pwd):/${{ github.workspace }} -w ${{ github.workspace }} --platform linux/${{ matrix.arch }} arm64v8/ubuntu:latest /bin/bash -c "
-          apt-get update && apt-get install -y ca-certificates &&
+          apt-get update && apt-get install -y ca-certificates gnupg &&
           apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 99E82A75642AC823 &&
           echo 'deb https://repo.scala-sbt.org/scalasbt/debian all main' > /etc/apt/sources.list.d/scala-sbt.list &&
           apt-get update &&