Proofread javadoc

Author: yevhenii.nadtochii

server/src/main/java/io/spine/server/delivery/AbstractWorkRegistry.java

@@ -79,7 +79,7 @@ private Optional<ShardProcessingSession> pickUp(ShardIndex index, WorkerId worke
     /**
      * Returns an identifier of the current worker that is now going to process the shard.
      *
-     * Typically, it would a thread ID.
+     * <p>An example of such an identifier could be ID of the thread which performs processing.
      *
      * @param node
      *         the node to which the resulted worker belongs

server/src/main/proto/spine/server/delivery/delivery.proto

@@ -102,6 +102,8 @@ message WorkerId {
     // A node to which this worker belongs.
     NodeId nodeId = 1 [(required) = true];
 
-    // Worker's identifier, typically it would a Thread ID.
+    // Worker's identifier.
+    //
+    // An example of such an identifier could be ID of the thread which processes a shard.
     string value = 2 [(required) = true];
 }