Added data type to the Parameters for those that I have added

Author: benn-thomsen

src/qcodes/instrument_drivers/tektronix/AWG70000A.py

@@ -191,7 +191,7 @@ def __init__(
         if channel not in list(range(1, num_channels + 1)):
             raise ValueError("Illegal channel value.")
 
-        self.state: Parameter = self.add_parameter(
+        self.state: Parameter[int, Self] = self.add_parameter(
             "state",
             label=f"Channel {channel} state",
             get_cmd=f"OUTPut{channel}:STATe?",