Report error message when body empty

[xieyongbin]

Describe the bug

Report body is longer than 72 characters when body empty

Config

rules:
  body-empty:
    level: ignore
  body-max-length:
    level: error
    length: 72

Error message

$> echo -n "feat(cli): add new flag" | commitlint 
body is longer than 72 characters

Expected behavior

body-max-length only check the length of body and body-empty check body empty

Version

# Run the following command
$ commitlint --version
commitlint-rs 0.2.2