Have stable version of DAVE out of development channel

Right now we’re pointing to https://addons.mozilla.org/firefox/downloads/latest-beta/673020/addon-673020-latest.xpi. We should point to a stable version instead.

Related issues

Blocked by #10679 (closed)
Blocks #11301 (closed)
Blocked by #11109 (closed)

Original created by @sajolida on 11300 (Redmine)

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