chore: check aethersx2 command per setup

tests/test_site_r4_emulators.py

@@ -163,7 +163,10 @@ class TheBuiltPages(unittest.TestCase):
     def test_aethersx2_downloads_from_the_collection(self):
         page = self._html("emulators/aethersx2")
         self.assertRegex(page, r'Download <a href="[^"]*/systems/sony[^"]*#sha1-[0-9a-f]{12}"')
-        self.assertNotIn("--emulator aethersx2", page)
+        # The command only where a setup launches AetherSX2 itself (KNULLI,
+        # ROCKNIX), never through RetroArch's folder, which the app never reads.
+        self.assertIn("With ROCKNIX or KNULLI:", page)
+        self.assertNotIn("RetroArch", page.split("Install this emulator", 1)[1].split("</details>", 1)[0])
 
     def test_the_index_leaves_the_template_out(self):
         # 00_example is `type: test`: no page, no index row.