[yaml]: uncomment WriteToKafka portion of test (#35277)

* uncomment kafka test and see if it runs with self hosted runner

* try again but with streaming mode enabled

* comment out the read portion

Author: derrickaw

.github/trigger_files/beam_PostCommit_Yaml_Xlang_Direct.json

@@ -1,4 +1,4 @@
 {
   "comment": "Modify this file in a trivial way to cause this test suite to run",
-  "revision": 3
+  "revision": 4
 }

sdks/python/apache_beam/yaml/extended_tests/messaging/kafka.yaml

@@ -15,9 +15,9 @@
 # limitations under the License.
 #
 
-# fixtures:
-#   - name: TEMP_BOOTSTAP_SERVER
-#     type: "apache_beam.yaml.integration_tests.temp_kafka_server"
+fixtures:
+  - name: TEMP_BOOTSTAP_SERVER
+    type: "apache_beam.yaml.integration_tests.temp_kafka_server"
 
 pipelines:
   # Kafka write pipeline
@@ -30,23 +30,24 @@ pipelines:
               - {value: 123}
               - {value: 456}
               - {value: 789}
-# TODO(#35272) - fix kafka test
-        # - type: MapToFields
-        #   config:
-        #     language: python
-        #     fields:
-        #       value:
-        #         callable: |
-        #           lambda row: str(row.value).encode('utf-8')
-        #         output_type: bytes
-        # - type: WriteToKafka
-        #   config:
-        #     format: "RAW"
-        #     topic: "silly_topic"
-        #     bootstrap_servers: "{TEMP_BOOTSTAP_SERVER}"
-        #     producer_config_updates:
-        #       linger.ms: "0"
+        - type: MapToFields
+          config:
+            language: python
+            fields:
+              value:
+                callable: |
+                  lambda row: str(row.value).encode('utf-8')
+                output_type: bytes
+        - type: WriteToKafka
+          config:
+            format: "RAW"
+            topic: "silly_topic"
+            bootstrap_servers: "{TEMP_BOOTSTAP_SERVER}"
+            producer_config_updates:
+              linger.ms: "0"
 
+  # TODO(#35272): Figure out why this times out when running on github.
+  # Locally runs fine.
   # Kafka read pipeline
   # Need a separate read pipeline to make sure the write pipeline is flushed
   # - pipeline:
@@ -77,5 +78,8 @@ pipelines:
   #             - {value: "456"}
   #             - {value: "789"}
 
+    options:
+      streaming: true
+
 # TODO: Error handling hard to trigger upon initial investigations.  Need to
 # investigate more.