Fix small typos (#29584)

Author: bwignall

doc/source/user_guide/integer_na.rst

@@ -63,7 +63,7 @@ up with a ``float64`` dtype Series:
    pd.Series([1, 2, np.nan])
 
 Operations involving an integer array will behave similar to NumPy arrays.
-Missing values will be propagated, and and the data will be coerced to another
+Missing values will be propagated, and the data will be coerced to another
 dtype if needed.
 
 .. ipython:: python

doc/source/whatsnew/v0.20.0.rst

@@ -33,7 +33,7 @@ Check the :ref:`API Changes <whatsnew_0200.api_breaking>` and :ref:`deprecations
 
 .. note::
 
-   This is a combined release for 0.20.0 and and 0.20.1.
+   This is a combined release for 0.20.0 and 0.20.1.
    Version 0.20.1 contains one additional change for backwards-compatibility with downstream projects using pandas' ``utils`` routines. (:issue:`16250`)
 
 .. contents:: What's new in v0.20.0