Made the code consistent

Author: SoumyadeepJana

tensorflow_datasets/image/deep_weeds.py

@@ -19,7 +19,6 @@
 _IMAGE_SHAPE = (256,256,3)
 
 _CITATION = """\
-
  @article{DeepWeeds2019,
   author = {Alex Olsen and
     Dmitry A. Konovalov and
@@ -45,7 +44,6 @@
   url = "https://doi.org/10.1038/s41598-018-38343-3",
   doi = "10.1038/s41598-018-38343-3"
 }
-
 """
 
 class DeepWeeds(tfds.core.GeneratorBasedBuilder):