fix: error message fix. (#375)

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Fixes #<issue_number_goes_here> 🦕

bigframes/dataframe.py

@@ -1532,7 +1532,7 @@ def _filter_rows(
     ) -> DataFrame:
         if len(self._block.index_columns) > 1:
             raise NotImplementedError(
-                "Method filter does not support rows multiindex. {constants.FEEDBACK_LINK}"
+                f"Method filter does not support rows multiindex. {constants.FEEDBACK_LINK}"
             )
         if (like is not None) or (regex is not None):
             block = self._block
@@ -1760,7 +1760,7 @@ def dropna(
     ) -> DataFrame:
         if inplace:
             raise NotImplementedError(
-                "'inplace'=True not supported. {constants.FEEDBACK_LINK}"
+                f"'inplace'=True not supported. {constants.FEEDBACK_LINK}"
             )
         if how not in ("any", "all"):
             raise ValueError("'how' must be one of 'any', 'all'")

bigframes/functions/remote_function.py

@@ -880,7 +880,7 @@ def read_gbq_function(
         ibis_signature = ibis_signature_from_routine(routine)
     except ReturnTypeMissingError:
         raise ValueError(
-            "Function return type must be specified. {constants.FEEDBACK_LINK}"
+            f"Function return type must be specified. {constants.FEEDBACK_LINK}"
         )
     except bigframes.dtypes.UnsupportedTypeError as e:
         raise ValueError(

bigframes/series.py

@@ -1242,7 +1242,7 @@ def filter(
             )
         if len(self._block.index_columns) > 1:
             raise NotImplementedError(
-                "Method filter does not support rows multiindex. {constants.FEEDBACK_LINK}"
+                f"Method filter does not support rows multiindex. {constants.FEEDBACK_LINK}"
             )
         if (like is not None) or (regex is not None):
             block = self._block