[FIX] hw_scale: read values from Adam scale

with migration from python2 to python3 not all regexes where converted
to byte-array.

backport of b4bcf86f to 11.0

closes odoo/odoo#27252

addons/hw_scale/controllers/main.py

@@ -95,7 +95,7 @@ ADAMEquipmentProtocol = ScaleProtocol(
     parity=serial.PARITY_NONE,
     timeout=0.2,
     writeTimeout=0.2,
-    weightRegexp=r"\s*([0-9.]+)kg", # LABEL format 3 + KG in the scale settings, but Label 1/2 should work
+    weightRegexp=b"\s*([0-9.]+)kg", # LABEL format 3 + KG in the scale settings, but Label 1/2 should work
     statusRegexp=None,
     statusParse=None,
     commandTerminator=b"\r\n",