Change location of collections tests.

The directories used for collections tests are changing as follows:

`test/` -> `tests/`
`test/results/` -> `tests/output/`

This is a breaking change for collections tests executed by ansible-test.
All collections will need to be updated to use the new directory.

The `tests/output/` directory should be added to the `.gitignore` or equivalent in each collection.

This change is being made before the first pre-release of Ansible 2.9 since ansible-test has not yet been shipped.
Using the `tests/` directory matches the other collections directories `plugins/` and `roles/`.

This resolves https://github.com/ansible/ansible/issues/60218

test/lib/ansible_test/_internal/provider/layout/collection.py

@@ -44,11 +44,11 @@ class CollectionLayout(LayoutProvider):
                                  namespace=collection_namespace,
                                  root=collection_root,
                              ),
-                             test_path='test',
-                             results_path='test/results',
-                             sanity_path='test/sanity',
-                             integration_path='test/integration',
-                             unit_path='test/unit',
-                             unit_module_path='test/unit/plugins/modules',
-                             unit_module_utils_path='test/unit/plugins/module_utils',
+                             test_path='tests',
+                             results_path='tests/output',
+                             sanity_path='tests/sanity',
+                             integration_path='tests/integration',
+                             unit_path='tests/unit',
+                             unit_module_path='tests/unit/plugins/modules',
+                             unit_module_utils_path='tests/unit/plugins/module_utils',
                              )

test/lib/ansible_test/_internal/provider/source/unversioned.py

@@ -46,6 +46,7 @@ class UnversionedSource(SourceProvider):
             'test': (
                 'results',
                 'cache',
+                'output',
             ),
             'docs/docsite': (
                 '_build',