remove spurious dot from string formatting example; thanks to Anthon van der Neut from docs@

sandrotosi · sandrotosi · commit baf30da2402d · 2011-12-24T15:53:35.000+01:00
diff --git a/Doc/library/string.rst b/Doc/library/string.rst
@@ -583,7 +583,7 @@ Expressing a percentage::
 
    >>> points = 19
    >>> total = 22
-   >>> 'Correct answers: {:.2%}.'.format(points/total)
+   >>> 'Correct answers: {:.2%}'.format(points/total)
    'Correct answers: 86.36%'
 
 Using type-specific formatting::
