Fix TextFormatMapTest.DynamicMessage issue#5136
Fix TextFormatMapTest.DynamicMessage issue#5136

Clean up a multi-line string to conform to Unix line endings.

Signed-off-by: Abhishek Jain <a290f03c670cdb95ea2944ad3ab209821df202b6@huawei.com>

google/protobuf,google/protobuf,google/protobuf,google/protobuf,google/protobuf,google/protobuf,google/protobuf,google/protobuf,google/protobuf,google/protobuf,google/protobuf