Fix or operator in parser (dashboard module) (#3027)

Fix `or` op. and test execution.
The error are:
- overlapping names of tests (2 tests called `test_process_value`)
- value passed to `_filter_operator` is string which cause using `,` as value (replaced string with list)

src/ralph/dashboards/filter_parser.py

@@ -11,6 +11,8 @@
 
 class FilterParser(object):
 
+    or_sep = ','
+
     def __init__(self, queryset, filters_dict, exclude_mode=False):
         self.filters = filters_dict
         if exclude_mode:
@@ -40,7 +42,8 @@ def _filter_operator(self, key, value, op):
         return reduce(op, [Q(**{key: v}) for v in value])
 
     def filter_or(self, key, value):
-        return [self._filter_operator(key, value, operator.or_)], {}
+        norm_val = value.split(self.or_sep)
+        return [self._filter_operator(key, norm_val, operator.or_)], {}
 
     def filter_and(self, key, value):
         return [self._filter_operator(key, value, operator.and_)], {}

src/ralph/dashboards/tests/test_parser.py

@@ -48,7 +48,7 @@ def test_process_value(self, value, expect):
         (['1'], Q(key='1')),
         (['1', '2'], Q(key='1') & Q(key='2')),
     )
-    def test_process_value(self, value, expect):
+    def test_process_value_as_list(self, value, expect):
         result = self.parser.filter_and('key', value)
         self.assertEqual(str(result[ARGS][0]), str(expect))