all: apply modernisers

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/system/dbus.go

@@ -172,12 +172,12 @@ func (s *linePrefixWriter) write(p []byte, a int) (int, error) {
 		return a, syscall.ENOMEM
 	}
 
-	if i := bytes.IndexByte(p, '\n'); i == -1 {
+	if before, after, ok := bytes.Cut(p, []byte{'\n'}); !ok {
 		n, _ := s.buf.Write(p)
 		s.n += n
 		return a + n, nil
 	} else {
-		n, _ := s.buf.Write(p[:i])
+		n, _ := s.buf.Write(before)
 		s.n += n + 1
 
 		v := s.buf.String()
@@ -190,7 +190,7 @@ func (s *linePrefixWriter) write(p []byte, a int) (int, error) {
 		}
 
 		s.buf.Reset()
-		return s.write(p[i+1:], a+n+1)
+		return s.write(after, a+n+1)
 	}
 }