Remove new line in documentation comment

The newline in the comment caused a space in the generated documentation, breaking the link. Removing the newline should fix the link in the generated doc (see line 146 for an example of this already in the file).

google/cloud/bigquery_datatransfer_v1/types/transfer.py

@@ -133,8 +133,7 @@ class TransferConfig(proto.Message):
             up a data transfer' section for each data
             source. For example the parameters for Cloud
             Storage transfers are listed here:
-            https://cloud.google.com/bigquery-
-            transfer/docs/cloud-storage-transfer#bq
+            https://cloud.google.com/bigquery-transfer/docs/cloud-storage-transfer#bq
         schedule (str):
             Data transfer schedule. If the data source does not support
             a custom schedule, this should be empty. If it is empty, the