Hans-Christoph Steiner 63298ad2ad update: change assert to fix flaky tests
This was happening often:

```
======================================================================
FAIL: test_strip_and_copy_image_in_file_ctime_changed (tests.test_update.UpdateTest.test_strip_and_copy_image_in_file_ctime_changed)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/builds/fdroid/fdroidserver/tests/test_update.py", line 1409, in test_strip_and_copy_image_in_file_ctime_changed
    self.assertNotAlmostEqual(
AssertionError: 1750683024.4857466 == 1750683024.4957466 within 0.01 delta (0.009999990463256836 difference)
```
2025-06-23 15:16:21 +02:00
..
2022-05-03 14:59:52 +00:00
2025-05-22 12:12:24 +02:00