bpo-13790: Change 'string' to 'specification' in format doc (GH-18690)

(cherry picked from commit 916895f)

Co-authored-by: Terry Jan Reedy <[email protected]>

Author: miss-islington

Doc/library/string.rst

@@ -303,9 +303,9 @@ specification is to be interpreted.
 Most built-in types implement the following options for format specifications,
 although some of the formatting options are only supported by the numeric types.
 
-A general convention is that an empty format string (``""``) produces
+A general convention is that an empty format specification produces
 the same result as if you had called :func:`str` on the value. A
-non-empty format string typically modifies the result.
+non-empty format specification typically modifies the result.
 
 The general form of a *standard format specifier* is:
 

Misc/NEWS.d/next/Documentation/2020-02-28-14-39-25.bpo-13790.hvLaRI.rst

@@ -0,0 +1 @@
+Change 'string' to 'specification' in format doc.