tests: disable minio console

The console port is high numbered and has been seen to occasionally collide
with some other program in the CI environment.  We do not use the
console anything, so simply switch it off.

(cherry picked from commit 48ff905)

tests/docker/docker-compose.yml

@@ -14,6 +14,7 @@ services:
       MINIO_REGION_NAME: panda-region
       MINIO_ROOT_PASSWORD: panda-secret
       MINIO_ROOT_USER: panda-user
+      MINIO_BROWSER: off
     expose:
     - '9000'
     healthcheck: