Added URL checker CI job and fixed all dead URLs. Updated version info and HISTORY.rst.

4 jobs for feature/add_urlchecker in 6 minutes and 15 seconds
Status Name Job ID Coverage
  Test
passed test_enpt #52579

00:05:16

91.0%
passed test_styles #52565

00:00:12

passed test_urls #52566

00:00:45

failed test_enpt #52564

00:00:52