DellEMC: Z9332f update PSU threshold (#7832)

#### Why I did it
Updated Z9332f PSU threshold values.

#### How I did it
Fetch the PSU voltage and temperature threshold via ipmitool

platform/broadcom/sonic-platform-modules-dell/z9332f/sonic_platform/psu.py

@@ -21,11 +21,12 @@ class Psu(PsuBase):
 
     # { PSU-ID: { Sensor-Name: Sensor-ID } }
     SENSOR_MAPPING = { 1: { "State": 0x2f, "Current": 0x37,
-                            "Power": 0x38, "Voltage": 0x36, 
+                            "Power": 0x38, "Voltage": 0x36,
                             "Temperature": 0x35 },
                        2: { "State": 0x39, "Current": 0x41,
-                            "Power": 0x42, "Voltage": 0x40, 
+                            "Power": 0x42, "Voltage": 0x40,
                             "Temperature": 0x3F } }
+
     # ( PSU-ID: FRU-ID }
     FRU_MAPPING = { 1: 3, 2: 4 }
 
@@ -119,13 +120,24 @@ def get_voltage_low_threshold(self):
         """
         Returns PSU low threshold in Volts
         """
-        return 11.4
+        is_valid, low_threshold = self.voltage_sensor.get_threshold("LowerCritical")
+        if not is_valid:
+            low_threshold = 11.4
+        low_threshold = "{:.2f}".format(low_threshold)
+
+        return float(low_threshold)
+
 
     def get_voltage_high_threshold(self):
         """
         Returns PSU high threshold in Volts
         """
-        return 12.6
+        is_valid, high_threshold = self.voltage_sensor.get_threshold("UpperCritical")
+        if not is_valid:
+            high_threshold = 12.6
+        high_threshold = "{:.2f}".format(high_threshold)
+
+        return float(high_threshold)
 
     def get_temperature(self):
         """
@@ -145,7 +157,13 @@ def get_temperature_high_threshold(self):
         """
         Returns the high temperature threshold for PSU in Celsius
         """
-        return 45.0
+        is_valid, high_threshold = self.temp_sensor.get_threshold("UpperCritical")
+        if not is_valid:
+            high_threshold = 113
+        high_threshold = "{:.2f}".format(high_threshold)
+
+        return float(high_threshold)
+
 
     def get_current(self):
         """