Add mediafiles mount to docker-compose

Related-PROD: PRODX-5842

Change-Id: Icf35fd64aad1de40eb54d1ec26182652cac6add7
diff --git a/testrail_bot/docker-compose.yml b/testrail_bot/docker-compose.yml
index 88dce9e..a38250a 100644
--- a/testrail_bot/docker-compose.yml
+++ b/testrail_bot/docker-compose.yml
@@ -9,6 +9,7 @@
     image: postgres:12.0-alpine
     volumes:
       - postgres_data:/var/lib/postgresql/data/
+      - media_volume:/mediafiles
     environment:
       - POSTGRES_USER=dev
       - POSTGRES_PASSWORD=dev