proto: Sync to TensorFlow 0c2241bede2 (2022-10-27) (#6001)

Pulls in source metadata additions added in
tensorflow/tensorflow@0c2241bede2.

Author: groszewn

tensorboard/compat/proto/event.proto

@@ -40,6 +40,17 @@ message Event {
     // An encoded version of a MetaGraphDef.
     bytes meta_graph_def = 9;
   }
+
+  // Information of the source that writes the events, this is only logged in
+  // the very first event along with the `file_version` field.
+  SourceMetadata source_metadata = 10;
+}
+
+// Holds the information of the source that writes the events.
+message SourceMetadata {
+  // Low level name of the summary writer, such as
+  // `tensorflow.core.util.events_writer`.
+  string writer = 1;
 }
 
 // Protocol buffer used for logging messages to the events file.