twister: Fix tests statuses if quarantine is verified

If test configuration is not quarantined and `--quarantine-verify`
mode is enabled, these should be filtered and not attached
to reports.

Proposed change applies this approach.

Signed-off-by: Katarzyna Giądła <katarzyna.giadla@nordicsemi.no>

scripts/pylib/twister/twisterlib/testplan.py

@@ -607,8 +607,7 @@ class TestPlan:
                 instance.reason = "Quarantine: " + matched_quarantine
                 return
             if not matched_quarantine and self.options.quarantine_verify:
-                instance.status = TwisterStatus.SKIP
+                instance.add_filter("Not under quarantine", Filters.CMD_LINE)
-                instance.reason = "Not under quarantine"
 
     def load_from_file(self, file, filter_platform=None):
         if filter_platform is None:

scripts/tests/twister/test_testplan.py

@@ -342,7 +342,7 @@ def test_quarantine_short(class_testplan, platforms_list, test_data,
             if testname in expected_val:
                 assert instance.status == TwisterStatus.NONE
             else:
-                assert instance.status == TwisterStatus.SKIP
+                assert instance.status == TwisterStatus.FILTER
                 assert instance.reason == "Not under quarantine"
         else:
             if testname in expected_val: