Use more specific assertions than assertTrue in tests

[Tim Graham]

We should change things like self.assertTrue(fetched.active_translation.title == 'Otsikko') to use assertEqual and things like self.assertTrue('id' in form.fields) to use assertIn. Attaching an initial patch. I used grep -rI "assertTrue" * | grep == to find instances that need changing.

[Berker Peksag]

​https://github.com/django/django/pull/3432

Should I create a new ticket for assertFalse(a == b), assertFalse(a != b), assertFalse("foo" in a) etc. instances?

[Tim Graham]

You can include those changes as part of this ticket, thanks.

[Tim Graham <timograham@…>]

In f7969b0920c403118656f6bfec58d6454d79ef1a:

Fixed #23620 -- Used more specific assertions in the Django test suite.