fix: any() on empty set now correctly returns False (#471)

Thank you for opening a Pull Request! Before submitting your PR, there are a few things you can do to make sure it goes smoothly:
- [ ] Make sure to open an issue as a [bug/issue](https://togithub.com/googleapis/python-bigquery-dataframes/issues/new/choose) before writing your code!  That way we can discuss the change, evaluate designs, and agree on the general idea
- [ ] Ensure the tests and linter pass
- [ ] Code coverage does not decrease (if any source code was changed)
- [ ] Appropriate docs were updated (if necessary)

Fixes #<issue_number_goes_here> 🦕

bigframes/core/compile/aggregate_compiler.py

@@ -414,7 +414,7 @@ def _(
     result = _is_true(column).any()
     return cast(
         ibis_types.BooleanScalar,
-        _apply_window_if_present(result, window).fillna(ibis_types.literal(True)),
+        _apply_window_if_present(result, window).fillna(ibis_types.literal(False)),
     )
 
 

tests/system/small/test_index.py

@@ -68,6 +68,10 @@ def test_index_has_duplicates(scalars_df_index, scalars_pandas_df_index):
     assert bf_result == pd_result
 
 
+def test_index_empty_has_duplicates():
+    assert not bpd.Index([]).has_duplicates
+
+
 def test_index_values(scalars_df_index, scalars_pandas_df_index):
     bf_result = scalars_df_index.index.values
     pd_result = scalars_pandas_df_index.index.values