[PicaMetrics] Explicit file mount instead of ambiguous named volume

pica-metrics-bot/docker-compose.yml

@@ -14,7 +14,7 @@ services:
     image: registry.picasoft.net/pica-metrics-bot:v1.0.1
     container_name: pica-metrics-services
     volumes:
-      - config.json:/code/config/config.json
+      - ./config.json:/code/config/config.json
     environment:
       - INTERVAL_SECONDS=60
     env_file: ./secrets/account.secrets