FXVPN-328: Enable telemetry by default

[lesleyjanenorton]

This PR enables telemetry in the extension by default, even if the client is not installed. Note that in this state, although telemetry is 'enabled', pings won't be sent to Glean until the client has been installed and is able to do so.

[strseb]

@lesleyjanenorton - i'd like to understand the motivation.
The flag will be poulated by the client anyway, which should be false per the telemetry guideline, no?

[lesleyjanenorton]

Nope, the AC is now that telemetry is opt-out. This change sets telemetry to On by default, even if the extension is installed before the client is installed (granted, no pings will be sent until the client is installed).

[strseb]

r+wc.

A: I do suspect that this is against the extension guidelines, at least it's a darkpattern. But that is a discussion i can have with santiago.

B: Not sure this has the intended effect.
This is only the default value until the extension connects to the client, which will then propagate it's value, so we should either change that in the client (that is a can of worm we don't want to open) ooor we just change the UI that is on by default and only apply that once a user action has been done.