Don't register tests as filters (#55332)

* Don't register tests as filters. Fixes #55319

* Remove tests for deprecated functionality

* Remove no-tests-as-filters sanity tests

* Remove docs too

* Revert "Remove docs too"

This reverts commit 7daf457a742e67ec6e91964852c7f804507b46b8.

* Make no-tests-as-filters doc an orphan

test/units/template/test_tests_as_filters_warning.py

@@ -1,35 +0,0 @@
-from ansible.template import Templar, display
-from units.mock.loader import DictDataLoader
-from jinja2.filters import FILTERS
-from os.path import isabs
-
-
-def test_tests_as_filters_warning(mocker):
-    fake_loader = DictDataLoader({
-        "/path/to/my_file.txt": "foo\n",
-    })
-    templar = Templar(loader=fake_loader, variables={})
-    filters = templar._get_filters(templar.environment.filters)
-
-    mocker.patch.object(display, 'deprecated')
-
-    # Call successful test, ensure the message is correct
-    filters['successful']({})
-    display.deprecated.assert_called_once_with(
-        'Using tests as filters is deprecated. Instead of using `result|successful` use `result is successful`', version='2.9'
-    )
-
-    # Call success test, ensure the message is correct
-    display.deprecated.reset_mock()
-    filters['success']({})
-    display.deprecated.assert_called_once_with(
-        'Using tests as filters is deprecated. Instead of using `result|success` use `result is success`', version='2.9'
-    )
-
-    # Call bool filter, ensure no deprecation message was displayed
-    display.deprecated.reset_mock()
-    filters['bool'](True)
-    assert display.deprecated.call_count == 0
-
-    # Ensure custom test does not override builtin filter
-    assert filters.get('abs') != isabs