[exporter/datasetexporter]: Call the currect function on shutdown (#24255)

**Description:** Call the correct function on shutdown

After we have changed the underlying library we haven't updated the
exporter code to call the correct function. This PR is fixing this.

**Link to tracking Issue:** #24253

**Testing:** 

1. Run open telemetry collector
2. Terminate it - `docker kill --signal SIGTERM ...`
3. Observe logs: 
```

2023-07-13T11:30:54.191Z	info	otelcol/collector.go:236	Received signal from OS	{"signal": "terminated"}
2023-07-13T11:30:54.191Z	info	service/service.go:157	Starting shutdown...
2023-07-13T11:30:54.191Z	info	adapter/receiver.go:139	Stopping stanza receiver	{"kind": "receiver", "name": "filelog/log", "data_type": "logs"}
...
...
2023-07-13T11:31:00.917Z	info	client/client.go:387	Buffers' Queue Stats:	{"kind": "exporter", "data_type": "logs", "name": "dataset/logs", "processed": 32, "enqueued": 32, "dropped": 0, "waiting": 0, "processingS": 24.727153498}
2023-07-13T11:31:00.919Z	info	client/client.go:399	Events' Queue Stats:	{"kind": "exporter", "data_type": "logs", "name": "dataset/logs", "processed": 200005, "enqueued": 200005, "waiting": 0, "processingS": 24.727153498}
2023-07-13T11:31:00.919Z	info	client/client.go:413	Transfer Stats:	{"kind": "exporter", "data_type": "logs", "name": "dataset/logs", "bytesSentMB": 150.06610584259033, "bytesAcceptedMB": 150.06610584259033, "throughputMBpS": 6.068879131385992, "perBufferMB": 4.689565807580948, "successRate": 1, "processingS": 24.727153498, "processing": 24.727153498}
2023-07-13T11:31:00.919Z	info	client/add_events.go:294	Finishing with success	{"kind": "exporter", "data_type": "logs", "name": "dataset/logs"}
2023-07-13T11:31:00.919Z	info	extensions/extensions.go:44	Stopping extensions...
2023-07-13T11:31:00.919Z	info	service/service.go:171	Shutdown complete.
```


**Documentation:** There is no change in the documentation needed.

Author: martin-majlis-s1

.chloggen/DSET-4050-handle-sigint-sigterm.yaml

@@ -0,0 +1,20 @@
+# Use this changelog template to create an entry for release notes.
+# If your change doesn't affect end users, such as a test fix or a tooling change,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: bug_fix
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: datasetexporter
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Call the correct library function then exporter is shutting down.
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [24253]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:

exporter/datasetexporter/datasetexporter.go

@@ -67,8 +67,7 @@ func newDatasetExporter(entity string, config *Config, set exporter.CreateSettin
 }
 
 func (e *DatasetExporter) shutdown(context.Context) error {
-	e.client.SendAllAddEventsBuffers()
-	return nil
+	return e.client.Shutdown()
 }
 
 func sendBatch(events []*add_events.EventBundle, client *client.DataSetClient) error {