DOC: normalize line endings and EOF

Author: Atharv-navatre

doc/source/user_guide/io.rst

@@ -6563,4 +6563,4 @@ Data hosted remotely can be read directly using a URL:
 .. code-block:: python
 
    import pandas as pd
-   df = pd.read_csv("https://raw.githubusercontent.com/pandas-dev/pandas/main/doc/data/air_quality_no2.csv")
+   df = pd.read_csv("https://raw.githubusercontent.com/pandas-dev/pandas/main/doc/data/air_quality_no2.csv")