update linter config, satisfy linter (#28)

app/io.go

@@ -1,3 +1,5 @@
+package app
+
 /*
 Copyright © 2024 Thomas von Dein
 
@@ -14,18 +16,24 @@ GNU General Public License for more details.
 You should have received a copy of the GNU General Public License
 along with this program. If not, see <http://www.gnu.org/licenses/>.
 */
-package app
 
-import "os"
+import (
+	"errors"
+	"os"
+)
 
 func cleanError(file string, err error) error {
 	// remove given [backup] file and forward the given error
-	return os.Remove(file)
+	oserr := os.Remove(file)
+	if oserr != nil {
+		return errors.Join(err, oserr)
+	}
+
+	return err
 }
 
 func fileExists(filename string) bool {
 	info, err := os.Stat(filename)
-
 	if err != nil {
 		// return false on any error
 		return false