CLN: add missing space in package's description (pandas-dev#20950)

Author: sietse

setup.py

@@ -134,7 +134,7 @@ def build_extensions(self):
         _build_ext.build_extensions(self)
 
 
-DESCRIPTION = ("Powerful data structures for data analysis, time series,"
+DESCRIPTION = ("Powerful data structures for data analysis, time series, "
                "and statistics")
 LONG_DESCRIPTION = """
 **pandas** is a Python package providing fast, flexible, and expressive data