ci: only target x86 for docker builds, edit docker-compose example

Author: TheLastCicada

.github/workflows/build-docker.yml

@@ -22,3 +22,4 @@ jobs:
     uses: Chia-Network/actions/.github/workflows/docker-build.yaml@main
     with:
       push: ${{ github.event_name != 'pull_request' }}
+      docker-platforms: linux/amd64

docker-compose-example.yml

@@ -42,5 +42,5 @@ services:
 
     volumes:
       # Mount Chia config directory to access certificates
-      - ~/.chia:/root/.chia
+      - ~/.chia/mainnet/config/ssl:/root/.chia/mainnet/config/ssl
     restart: unless-stopped