[Core] Added support for submission-time task names. (#10449)

* Added support for submission-time task names.

* Suggestions from code review: add missing consts

Co-authored-by: SangBin Cho <rkooo567@gmail.com>

* Add num_returns arg to actor method options docstring example.

* Add process name line and proctitle assertion to submission-time task name section of advanced docs.

* Add submission-time task name --> proctitle test for Python worker.

* Added Python actor options tests for num_returns and name.

* Added Java test for submission-time task names.

* Add dashboard image to task name docs section.

* Move to fstrings.

Co-authored-by: SangBin Cho <rkooo567@gmail.com>

doc/source/advanced.rst

@@ -51,6 +51,26 @@ And vary the number of return values for tasks (and actor methods too):
     assert ray.get(id1) == 0
     assert ray.get(id2) == 1
 
+And specify a name for tasks (and actor methods too) at task submission time:
+
+.. code-block:: python
+
+   import setproctitle
+
+   @ray.remote
+   def f(x):
+      assert setproctitle.getproctitle() == "ray::special_f"
+      return x + 1
+
+   obj = f.options(name="special_f").remote(3)
+   assert ray.get(obj) == 4
+
+This name will appear as the task name in the machine view of the dashboard, will appear
+as the worker process name when this task is executing (if a Python task), and will
+appear as the task name in the logs.
+
+.. image:: images/task_name_dashboard.png
+
 
 Dynamic Custom Resources
 ------------------------