FIX(minio): correct invalid SCANNER_SPEED value

- Change MINIO_SCANNER_SPEED from 'off' to 'slowest'
- 'off' is not a valid value, causing config errors

minio/helm-values.yaml

@@ -58,7 +58,7 @@ environment:
   MINIO_API_REPLICATION_MAX_WORKERS: "1"
   MINIO_API_REPLICATION_MAX_LRG_WORKERS: "1"
   MINIO_API_TRANSITION_WORKERS: "1"
-  MINIO_SCANNER_SPEED: "off"
+  MINIO_SCANNER_SPEED: "slowest"
 
 # API Ingress (S3 endpoint)
 ingress: