Fix in README.md example code

[ginovva320]

The Queue constructor requires a reference to the queue, not the tasks child. Fixed the code example given for the chat sanitization script.

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[coveralls]

Coverage remained the same at 100.0% when pulling 04bfb26 on ginovva320:patch-1 into b11116f on firebase:master.

[ginovva320]

I signed it!

[cbraynor]

Awesome, thanks for spotting that!