test(logging): add back DeleteLog test (#3114)
test(logging): add back DeleteLog test (#3114)

fixes #1654 

To de-flake:
- Instead of calling Logs() which is flakey, we write a new log entry then do a single deletion
- Also verified with BE that the quota for all logadmin api calls is 600/min and 1k/hour

It might still flake for a new reason since DeleteLogs is getting deprecated and may be inherently flakey. I will monitor it.
googleapis/google-cloud-go,googleapis/google-cloud-go,googleapis/google-cloud-go,googleapis/google-cloud-go