Add rule for HuskyCI

[gustavocovas]

Add rule to check whether Gitlab CI definitions contains the string 'huskyCI': https://huskyci.opensource.globo.com/

The rule will return true if the string is not found. (This would mean that HuskyCI is probably not used in the repository)

I could not write interesting tests for this, since it would require us to mock the gitlab.Client struct. Any thoughts for these?