Allow functions that don't accept parameters as event callbacks

[mofojed]

As of change #236 , you must now provide lambdas that accept the event positional argument. However, we should allow you to pass in a function that doesn't accept any positional arguments without crashing as well. E.g. this snippet should work:

import deephaven.ui as ui
from deephaven.ui import use_state


@ui.component
def counter():
    count, set_count = use_state(0)
    return [
      # Pass in a function that accepts the event argument
      ui.action_button(f"Foo {count}", on_press=lambda e: set_count(count + 1)),
      # Pass in a function that does not have any positional arguments
      ui.action_button(f"Bar {count}", on_press=lambda: set_count(count + 1))
    ]


c = counter()