I use a 1K, 2K resistor voltage divider with my HC05 modules running at 9600 baud all the time. I have had no issues.
Nor have I had any issues running at 38400 baud during setup in AT mode with the resistor voltage divider .
I set up an HC05 on my Uno and connected to serial Bluetooth terminal on my Android tablet. Running your code, I do not see the extra digit.