V3.15: bug fixes and framework updates

While we're working hard on our next major app update that will deliver a couple of brand-new features shortly, here's another small one with a bunch of bug fixes.

What's new

• Microphone, camera, and sharing controls are now always shown and are no longer missing in some layouts.

• Quality indicator was missing at times in the in-session menu, should appear correctly now.

• You'll only see the bad network warning now when it actually is struggling. We've fixed cases where it was shown unnecessarily.

• Framework updates around Electron and Jitsi to make sure we benefit from the latest fixes and improvements.

Questions or feedback? Submit it either through the dialog shown after a session or this form.