Bug 1716322 - Enable fflate and ping payload gzipping in QML

[brizental]

This is blocked until a new version fflate is out with these changes: 101arrowz/fflate#75

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[101arrowz]

Just added a few comments regarding the usage of fflate.

[brizental]

New fflate version not required, as discussed in 101arrowz/fflate#75 (comment)

This is ready for review. Already tested on the debug viewer, look for tag monday-qml-gzipping heh.

[Dexterp37]

Wow, that was quite a Mistery. Thank you Bea and thanks @101arrowz .

@brizental please add a changelog entry before merging.