test: fix test_extension.py

test_extension.py assumes that no extension is known at test start.
This assumption is wrong because we do not come out of reboot.
A prior test may have already hunted for the extension bootdev.

Remove the invalid assert.

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
diff --git a/test/py/tests/test_extension.py b/test/py/tests/test_extension.py
index 267cf2f..2a3c511 100644
--- a/test/py/tests/test_extension.py
+++ b/test/py/tests/test_extension.py
@@ -26,7 +26,9 @@
     load_dtb(u_boot_console)
 
     output = u_boot_console.run_command('extension list')
-    assert('No extension' in output)
+    # extension_bootdev_hunt may have already run.
+    # Without reboot we cannot make any assumption here.
+    # assert('No extension' in output)
 
     output = u_boot_console.run_command('extension scan')
     assert output == 'Found 2 extension board(s).'