Just: run the whole of the forwarding tests

The entry point sat two thirds of the way up the file, so running it as a
script stopped there: the thirteen tests defined below it never ran, and
`bazel test` reported a clean twenty-six with nothing to say it was a subset.
Among the missing were the checks that the fixtures still match what `just`
really dumps, and the one pinning that a recipe reached under two spellings
runs once.

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>

Author: redsun82

misc/just/test_forward_command.py

@@ -241,10 +241,6 @@ def test_leaves_a_path_absolute_when_the_argument_was(self):
         )
 
 
-if __name__ == "__main__":
-    unittest.main()
-
-
 class TestFindJustfilesAbove(unittest.TestCase):
     """The two shapes a consuming root can have, both of which the README promises.
 
@@ -472,3 +468,7 @@ def test_a_root_defining_its_own_is_not(self):
             self.recipes(self.outer)["_root_format"],
             self.recipes(self.inner)["_root_format"],
         )
+
+
+if __name__ == "__main__":
+    unittest.main()