Problem description: If action.get API with parameter "selectAcknowledgeOperations" equal to "extend" is called for an action that has an update operation that sends out a message, "operationid" is not returned in "opmessage" section for such operations, but this field is present for the action triggering operations and recovery operations.
Once fixed, the examples in action.get documentation should be updated.

Steps to reproduce:

1. Navigate to Configuration => Actions and create a Trigger action
2. Add an operation, a recovery operation and an update operation. All of them should send out a message.
3. Execute the following action.get API:

   {
       "jsonrpc": "2.0",
       "method": "action.get",
       "params": {
       	"countOutput": false,
       	"output": "extend",
       	"selectOperations": "extend",
       	"selectRecoveryOperations": "extend",
       	"selectAcknowledgeOperations": "extend",
       	"selectFilter": "extend"
       },
       "auth": "201c3b5f4dd726f88b6c7df933a74523",
       "id": 1
   

Result: there is no field "operationid" in the "acknowledgeOperations" => "opmessage" section of the received API response, but such field is present both for "recoveryOperations" => "opmessage" and "operations" => "opmessage" sections: API_output

Expected: from consistency point of view field "operationid" should be returned for all types of operations (triggering operation, update operation and recovery operation). Examples in action.get documentation should also be updated.