fix alpine linux ci build (#434)

.github/workflows/build.yml

@@ -316,7 +316,7 @@ jobs:
 
       - name: Build
         run: |
-          podman run --rm -v $PWD:/mnt -w /mnt $IMAGE ./packages/alpine/01-in-docker.sh
+          podman run --security-opt seccomp=unconfined --rm -v $PWD:/mnt -w /mnt $IMAGE ./packages/alpine/01-in-docker.sh
 
       - name: Upload
         uses: actions/upload-artifact@v2

packages/alpine/01-in-docker.sh

@@ -8,6 +8,8 @@ then
 fi
 apk add alpine-sdk git
 abuild-keygen -an
+# TODO: use `abuild-keygen --install`
+cp ~/.abuild/*.pub /etc/apk/keys/
 
 ./packages/alpine/buildapk.sh