Update Minio tests for BB CI

In BigBang CI the minio test currently fails due to what seem like timing errors. Might be good to add a couple retries on the mc config command.

---
Logs for minio-instance-script-test:
---
---
Running test-write.sh...
---
+ sleep 60
+ mc config host add bigbang http://minio:80 minio minio123
mc: <ERROR> Unable to initialize new alias from the provided credentials. Get "http://minio/probe-bucket-sign-trm9ctzma39i/?location=": dial tcp 10.43.226.206:80: connect: connection refused.