[lldb][test] Modernize assertEqual(value, bool) (#82526)

Any time we see the pattern `assertEqual(value, bool)`, we can replace
that with `assert<bool>(value)`. Likewise for `assertNotEqual`.

Technically this relaxes the test a bit, as we may want to make sure
`value` is either `True` or `False`, and not something that implicitly
converts to a bool. For example, `assertEqual("foo", True)` will fail,
but `assertTrue("foo")` will not. In most cases, this distinction is not
important.

There are two such places that this patch does **not** transform, since
it seems intentional that we want the result to be a bool:
*
https://github.com/llvm/llvm-project/blob/5daf2001a1e4d71ce1273a1e7e31cf6e6ac37c10/lldb/test/API/python_api/sbstructureddata/TestStructuredDataAPI.py#L90
*
https://github.com/llvm/llvm-project/blob/5daf2001a1e4d71ce1273a1e7e31cf6e6ac37c10/lldb/test/API/commands/settings/TestSettings.py#L940

Followup to 9c246882. I patched `teyit`
with a `visit_assertEqual` node handler to generate this.