deleting a rule always emits the API response to console

[rabbah]

Describe the bug

If you delete a rule, you'll get output like this printed to the console:

Rules Deleted! {
  "action": {
    "name": "x",
    "path": "rodricgm-h4nvfnjgdgg"
  },
  "annotations": [],
  "name": "r",
  "namespace": "rodricgm-h4nvfnjgdgg",
  "publish": false,
  "status": "inactive",
  "trigger": {
    "name": "periodic",
    "path": "rodricgm-h4nvfnjgdgg"
  },
  "updated": 1581260192275,
  "version": "0.0.1"
}

This is different from other delete commands which print the JSON output only if the --json flag is present. The rule delete command does not support this flag.

To Reproduce
Steps to reproduce the behavior:

1. Create a trigger, action and a rule
2. Delete the rule

Expected behavior
No output to console unless --json is provided.