[EAGLE-1051] update removePolicy

https://issues.apache.org/jira/browse/EAGLE-1051

There is no need to do this check. As eagle has a table `policy_publishment` which has defined the relationship between policies and publishments.

```
CREATE TABLE IF NOT EXISTS policy_publishment (
  policyId VARCHAR(50),
  publishmentName VARCHAR(50),
  PRIMARY KEY(policyId, publishmentName),
  CONSTRAINT `policy_id_fk` FOREIGN KEY (`policyId`) REFERENCES `policy_definition` (`id`) ON DELETE CASCADE ON UPDATE CASCADE,
  CONSTRAINT `publishment_id_fk` FOREIGN KEY (`publishmentName`) REFERENCES `publishment` (`id`) ON DELETE CASCADE ON UPDATE CASCADE
);
```

Author: Zhao, Qingwen <qingwzhao@apache.org>

Closes #959 from qingwen220/EAGLE-1051.
2 files changed