Destroy the client for all protocols.

[jesusprubio]

Some of them doesn't support it (make a PR) and in others we are not passing the parameter properly.

• TFTP: https://github.com/jesusprubio/bluebox-ng/blob/a7aad0753969bd64f69a5d66d70585903aecf5bb/lib/protocols/tftp.js#L29
• LDAP: https://github.com/jesusprubio/bluebox-ng/blob/e20276e8f87203adb4bf1ffe1c1488c06570e892/lib/protocols/ldap.js#L32
• SNMP: https://github.com/jesusprubio/bluebox-ng/blob/e20276e8f87203adb4bf1ffe1c1488c06570e892/lib/protocols/snmp.js#L37
• Mongo: https://github.com/jesusprubio/bluebox-ng/blob/e20276e8f87203adb4bf1ffe1c1488c06570e892/lib/protocols/mongo.js#L36