The old link seems not to work anymore, so instead replace it with an
invitation link freshly generated.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
I often wish I had a short and Zephyr-specific place to point people
to when they're asking for help in ways that make it hard to help
them.
Add one.
Signed-off-by: Marti Bolivar <marti.bolivar@nordicsemi.no>