Strip null bytes from parsed eeprom data before writing to db (#20512)

Why I did it
This was failing sonic-mgmt test test_syseepromd due to a setup error on account of null bytes being parsed from the S6000 eeprom.

This is due to differences in the way sonic-db-cli handles null values in the part number as parsed by the EEPROM in the 202012 image vs 202205+ image versions:

How I did it
Added logic to strip null bytes from parsed data before writing to database.

How to verify it
Run the aforementioned sonic-mgmt test before and after making the change in this PR -- note that test fails on setup without the change. See attached logs.
s6000_test_syseepromd_logs.txt

Flashed image with this change on an S6000 device and ran the above sonic-mgmt test:

platform/broadcom/sonic-platform-modules-dell/s6000/sonic_platform/eeprom.py

@@ -429,7 +429,7 @@ def update_eeprom_db(self, e):
                     data = ":".join(["{:02x}".format(T) for T in e[offset:offset+f[1]]]).upper()
                 else:
                     data = e[offset:offset+f[1]].decode('ascii')
-                client.hset('EEPROM_INFO|{}'.format(f[0]), 'Value', data)
+                client.hset('EEPROM_INFO|{}'.format(f[0]), 'Value', data.strip('\x00'))
                 offset += f[1]
 
             if not self._is_valid_block_checksum(e[blk_start:blk_end]):