Fix: add roundingmode as str test (#2098)

* fix: adds test of roundingmode as a str

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---------

Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>

Author: chalmerlowe

google/cloud/bigquery/schema.py

@@ -259,11 +259,10 @@ def __init__(
             if self._properties.get("foreignTypeDefinition") is None:
                 raise ValueError(
                     "If the 'field_type' is 'FOREIGN', then 'foreign_type_definition' is required."
-                )            
+                )
         if fields:  # Don't set the property if it's not set.
             self._properties["fields"] = [field.to_api_repr() for field in fields]
 
-
     @classmethod
     def from_api_repr(cls, api_repr: dict) -> "SchemaField":
         """Return a ``SchemaField`` object deserialized from a dictionary.

tests/unit/test_schema.py

@@ -314,6 +314,11 @@ def test_fields_property(self):
         schema_field = self._make_one("boat", "RECORD", fields=fields)
         self.assertEqual(schema_field.fields, fields)
 
+    def test_roundingmode_property_str(self):
+        ROUNDINGMODE = "ROUNDING_MODE_UNSPECIFIED"
+        schema_field = self._make_one("test", "STRING", rounding_mode=ROUNDINGMODE)
+        self.assertEqual(schema_field.rounding_mode, ROUNDINGMODE)
+
     def test_to_standard_sql_simple_type(self):
         examples = (
             # a few legacy types