Update peS2o.py

peS2o.py

@@ -118,7 +118,7 @@ _CITATION = """\
     year = 2023,
     title = {{peS2o (Pretraining Efficiently on S2ORC) Dataset}},
     institution = {{Allen Institute for AI}},
-    note = {ODC-By, \url{https://github.com/allenai/pes2o}}
+    note = {ODC-By, \\url{https://github.com/allenai/pes2o}}
 }
 """