Clean up deprecated loop properties and parameters

[crusaderky]

Clean up loop properties and parameters which have been deprecated for the last 2 years.

[github-actions]

Unit Test Results

See test report for an extended history of previous test failures. This is useful for diagnosing flaky tests.

    31 files  ± 0      31 suites  ±0   11h 23m 8s ⏱️ + 11m 27s
 4 072 tests  -  5   3 966 ✅  -  4    104 💤 ±0  2 ❌  - 1 
59 101 runs   - 75  56 667 ✅  - 74  2 432 💤 ±0  2 ❌  - 1 

For more details on these failures, see this check.

Results for commit d661ffd. ± Comparison against base commit 5fe4b05.

This pull request removes 5 tests.

distributed.deploy.tests.test_cluster ‑ test_deprecated_loop_properties
distributed.diagnostics.tests.test_progressbar ‑ test_deprecated_loop_properties
distributed.tests.test_client ‑ test_deprecated_loop_properties
distributed.tests.test_scheduler ‑ test_io_loop
distributed.tests.test_worker ‑ test_io_loop_alternate_loop

♻️ This comment has been updated with latest results.