.golangci.yml: don't lint autogenerated files
.golangci.yml: don't lint autogenerated files

So when we enable linters for formatting, they do not complain about
those files.

Refs #9557

Signed-off-by: Mateusz Gozdek <13f764135ff35d07236cdb9e39f2edb4395b2583@gmail.com>

keegancsmith/prometheus,keegancsmith/prometheus,alileza/prometheus,alileza/prometheus,prometheus/prometheus,keegancsmith/prometheus,prometheus/prometheus,alileza/prometheus,keegancsmith/prometheus,alileza/prometheus,prometheus/prometheus,prometheus/prometheus,prometheus/prometheus,keegancsmith/prometheus,alileza/prometheus