fix(tests): remove test for deprecated API

nvim_subscribe, nvim_unsubscribe are deprecated since Nvim 0.11:
neovim/neovim#28487

Author: justinmk

test/test_events.py

@@ -34,23 +34,3 @@ def test_async_error(vim: Nvim) -> None:
     vim.command("lolwut", async_=True)
     event = vim.next_message()
     assert event[1] == 'nvim_error_event'
-
-
-def test_broadcast(vim: Nvim) -> None:
-    vim.subscribe('event2')
-    vim.command('call rpcnotify(0, "event1", 1, 2, 3)')
-    vim.command('call rpcnotify(0, "event2", 4, 5, 6)')
-    vim.command('call rpcnotify(0, "event2", 7, 8, 9)')
-    event = vim.next_message()
-    assert event[1] == 'event2'
-    assert event[2] == [4, 5, 6]
-    event = vim.next_message()
-    assert event[1] == 'event2'
-    assert event[2] == [7, 8, 9]
-    vim.unsubscribe('event2')
-    vim.subscribe('event1')
-    vim.command('call rpcnotify(0, "event2", 10, 11, 12)')
-    vim.command('call rpcnotify(0, "event1", 13, 14, 15)')
-    msg = vim.next_message()
-    assert msg[1] == 'event1'
-    assert msg[2] == [13, 14, 15]