Set schemas path relative to executable

Previously, the schemas path was defined relative to the working directory, but the schemas will be stored in a path
relative to the arduino-check executable.

Author: per1234

Diff for: configuration/configuration.go

@@ -99,6 +99,9 @@ func TargetPath() *paths.Path {
 
 // SchemasPath returns the path to the folder containing the JSON schemas.
 func SchemasPath() *paths.Path {
-	workingPath, _ := os.Getwd()
-	return paths.New(workingPath)
+	executablePath, err := os.Executable()
+	if err != nil {
+		panic(err)
+	}
+	return paths.New(executablePath).Parent()
 }