fix RFC2737 with update xcvr vendor version key name (sonic-net#241)

- What I did

In the TRANSCEIVER_INFO table of STATE_DB, the key of transceiver reversion was changed from "hardware_rev" to "vendor_rev", detail info please refer to PR sonic-net/sonic-platform-daemons#231

RFC2737 implementation needs to be updated with the new key name in order to get the correct info from the state DB

- How I did it

Update the key name from "hardware_rev" to "vendor_rev", update the unit test cases.

- How to verify it

Run the community SNMP test.

- Description for the changelog

src/sonic_ax_impl/mibs/ietf/rfc2737.py

@@ -96,7 +96,7 @@ class XcvrInfoDB(str, Enum):
     Transceiver info keys
     """
     TYPE              = "type"
-    HARDWARE_REVISION = "hardware_rev"
+    VENDOR_REVISION   = "vendor_rev"
     SERIAL_NUMBER     = "serial"
     MANUFACTURE_NAME  = "manufacturer"
     MODEL_NAME        = "model"

tests/mock_tables/asic0/state_db.json

@@ -1,7 +1,7 @@
 {
   "TRANSCEIVER_INFO|Ethernet0": {
     "type": "QSFP+",
-    "hardware_rev": "A1",
+    "vendor_rev": "A1",
     "serial": "SERIAL_NUM",
     "manufacturer": "VENDOR_NAME",
     "model": "MODEL_NAME"

tests/mock_tables/asic1/state_db.json

@@ -1,7 +1,7 @@
 {
   "TRANSCEIVER_INFO|Ethernet8": {
     "type": "QSFP+",
-    "hardware_rev": "A1",
+    "vendor_rev": "A1",
     "serial": "SERIAL_NUM",
     "manufacturer": "VENDOR_NAME",
     "model": "MODEL_NAME"

tests/mock_tables/state_db.json

@@ -34,15 +34,15 @@
   },
   "TRANSCEIVER_INFO|Ethernet0": {
     "type": "QSFP+",
-    "hardware_rev": "A1",
+    "vendor_rev": "A1",
     "serial": "SERIAL_NUM",
     "manufacturer": "VENDOR_NAME",
     "model": "MODEL_NAME",
     "is_replaceable": "True"
   },
   "TRANSCEIVER_INFO|Ethernet1": {
     "type": "QSFP-DD",
-    "hardware_rev": "A1",
+    "vendor_rev": "A1",
     "serial": "SERIAL_NUM",
     "manufacturer": "VENDOR_NAME",
     "model": "MODEL_NAME",