test(inventory): read the width test's tempdir file without the cache

The file is written by the test itself, so the path-keyed read cache does
not fit; opt the read out of the uncached-read lint instead.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

tests/unit/python/cli/administration/inventory/provision/test_ruamel_io.py

@@ -81,7 +81,8 @@ class TestDumpDocument(unittest.TestCase):
 
             dump_document(path, document)
 
-            lines = path.read_text(encoding="utf-8").splitlines()
+            text = path.read_text(encoding="utf-8")  # nocheck: cache-read tempdir
+            lines = text.splitlines()
             self.assertEqual(3, len(lines))
             self.assertEqual(f"- {key}", lines[1])
             self.assertEqual(key, load_document(path)["authorized_keys"][0])