Replace @flaky.flaky decorate with pytest marker

Use the `@pytest.mark.flaky` marker in place of the `@flaky.flaky`
decorator, to modernize the code and improve compatibility with other
plugins providing the feature such as `pytest-rerunfailures`.

Signed-off-by: Michał Górny <[email protected]>

Author: mgorny

tests/test_watchers.py

@@ -18,7 +18,6 @@
 import time
 
 # Third party imports
-from flaky import flaky
 import pytest
 
 # Local imports
@@ -43,7 +42,7 @@ def __call__(self, *args, **kwargs):
 @pytest.mark.parametrize(
     'Watcher', (PollingWatcher, QtWatcher),
 )
-@flaky(max_runs=3)
+@pytest.mark.flaky(max_runs=3)
 def test_watchers(Watcher, tmpdir):
     """Stress test Watcher implementations"""