Add test that flushed query param is processed even with empty data

[estolfo]

I've also added a change to only add data to the data channel if the length of the bytes received is > 0.

[ghost]

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• Start Time: 2022-01-17T13:49:27.288+0000

• Duration: 7 min 20 sec

• Commit: 17793fc

Test stats 🧪

Test	Results
Failed	0
Passed	84
Skipped	0
Total	84

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