[FIX] test_lint: force absolute path to compute odoo path

When using the flamegraph module from a parent directory of odoo, the
dirname method returns a relative path, leading to a traceback.

With this commit, the odoo_path is enforced to be an absolute path.

closes odoo/odoo#40124

Signed-off-by: Christophe Monniez (moc) <moc@odoo.com>

odoo/addons/test_lint/tests/test_markers.py

@@ -24,7 +24,7 @@ class TestConflictMarkers(TransactionCase):
 
         counter = 0
 
-        odoo_path = os.path.dirname(odoo.__file__)
+        odoo_path = os.path.abspath(os.path.dirname(odoo.__file__))
         paths = odoo.addons.__path__ + [odoo_path]
         paths.remove(os.path.join(odoo_path, 'addons'))  # avoid checking odoo/addons twice