templater: update error message of invalid number passed to word() function

"word(3, desc)" is valid now.

mercurial/templater.py

@@ -569,8 +569,7 b' def word(context, mapping, args):'
         num = int(stringify(args[0][0](context, mapping, args[0][1])))
     except ValueError:
         # i18n: "word" is a keyword
-        raise error.ParseError(
-                _("Use strings like '3' for numbers passed to word function"))
+        raise error.ParseError(_("word expects an integer index"))
     text = stringify(args[1][0](context, mapping, args[1][1]))
     if len(args) == 3:
         splitter = stringify(args[2][0](context, mapping, args[2][1]))

tests/test-command-template.t

@@ -2778,5 +2778,5 b' Test word for integer literal'
 Test word for invalid numbers
 
   $ hg log -Gv -R a --template "{word('a', desc)}"
-  hg: parse error: Use strings like '3' for numbers passed to word function
+  hg: parse error: word expects an integer index
   [255]