Set logging level to fatal when running platform rule function tests

The tests use a platform that is missing a boards.txt file. With the logger's default "info" level, this results in a
useless log line for every one of those tests.

Author: per1234

Diff for: internal/rule/rulefunction/platform_test.go

@@ -25,12 +25,14 @@ import (
 	"github.com/arduino/arduino-lint/internal/project/projecttype"
 	"github.com/arduino/arduino-lint/internal/rule/ruleresult"
 	"github.com/arduino/go-paths-helper"
+	"github.com/sirupsen/logrus"
 	"github.com/stretchr/testify/assert"
 )
 
 var platformTestDataPath *paths.Path
 
 func init() {
+	logrus.SetLevel(logrus.FatalLevel)
 	workingDirectory, err := paths.Getwd()
 	if err != nil {
 		panic(err)