Why not to set rustflags empty by default?

[qalisander]

Awesome gh action! But one thing could be better as I feel.

The default behavior in complex pipelines can easy turn every pipeline into red. At first glance it seems, that natural disaster happened. While in reality just a single warning appeared. Isn't it better to have a single pipeline dedicated to a warning analysis? And have just a single use of rustflags property in this case. When that specific pipeline fails it is quite clear what happened.

IMHO default -D warnings overriding behavior of flags from config.toml looks quite tricky for new users.