A 'tattletale' exists as a noun (meaning someone who informs on another). For example "He was the tattletale of the class. You could never trust him to keep a secret." I would say this isn't very common, and sounds a bit old-fashioned, but then I'm a Brit and I believe this noun may be more common in American English.
You can also 'tell on' someone. Which also means to inform the authorities/not keep a secret.I would say this is very common in British English. It's often, but not always, used in the context of bad behaviour by a child, so it's quite informal. For example "If you don't stop, I will go to the teacher and tell on you.'
I have never heard these two phrases combined into one verb ' to tattle-tale on' - it could be a dialect form or a new emerging form of the language perhaps?