[Feature][transform-v2] add metric doc

Author: nijiahui

docs/en/seatunnel-engine/rest-api-v1.md

@@ -259,6 +259,7 @@ This API has been deprecated, please use /hazelcast/rest/maps/job-info/:jobId in
     "SinkWriteQPS": "",
     "SinkWriteBytes": "",
     "SinkWriteBytesPerSeconds": "",
+    "TransformOutputCount": {},
     "TableSourceReceivedCount": {},
     "TableSourceReceivedBytes": {},
     "TableSourceReceivedBytesPerSeconds": {},

docs/en/seatunnel-engine/rest-api-v2.md

@@ -165,6 +165,7 @@ seatunnel:
     "SinkWriteQPS": "",
     "SinkWriteBytes": "",
     "SinkWriteBytesPerSeconds": "",
+    "TransformOutputCount": {},
     "TableSourceReceivedCount": {},
     "TableSourceReceivedBytes": {},
     "TableSourceReceivedBytesPerSeconds": {},
@@ -245,6 +246,7 @@ This API has been deprecated, please use /job-info/:jobId instead
     "SinkWriteQPS": "",
     "SinkWriteBytes": "",
     "SinkWriteBytesPerSeconds": "",
+    "TransformOutputCount": {},
     "TableSourceReceivedCount": {},
     "TableSourceReceivedBytes": {},
     "TableSourceReceivedBytesPerSeconds": {},