docs: dev-tools: kunit: don't use a table for docs name

We'll be replacing :doc:`foo` references to
Documentation/foo.rst. Yet, here it happens inside a table.
Doing a search-and-replace would break it.

Yet, as there's no good reason to use a table there,
let's just convert it into a list.

Reviewed-by: David Gow <[e-mail]>
Acked-by: Brendan Higgins <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>
Link: https://lore.kernel.org/r/07d3a8[e-mail]
Signed-off-by: Jonathan Corbet <[e-mail]>

Documentation/dev-tools/kunit/api/index.rst

···
 This section documents the KUnit kernel testing API. It is divided into the
 following sections:
 
-================================= ==============================================
-:doc:`test`                       documents all of the standard testing API
-                                  excluding mocking or mocking related features.
-================================= ==============================================
+Documentation/dev-tools/kunit/api/test.rst
+
+ - documents all of the standard testing API excluding mocking
+   or mocking related features.