[Development] COIN failures on dev

[Adam Treat]

Hi,

For the past few business days we've all witnessed failures on dev 
branch like this: https://codereview.qt-project.org/#/c/213309/

Seems that something broke with provisioning on macOS or something. I 
see this https://codereview.qt-project.org/#/c/214045/ attempt to fix, 
but that is also failing to integrate due to seemingly unrelated reasons.

I'm disturbed that I haven't seen any widely shared communication about 
this, how it broke, what is being done to fix, or what can be done to 
stop it in the future.

Things seem really broken with our CI system in general. I wonder that 
this isn't the normalization of deviance. Has the project just given up 
and regards this as standard operating procedure?

- Adam