Suppress deprecation for format specification

Author: kubo39

spec/arrays.dd

@@ -1192,7 +1192,7 @@ printf("the string is '%s'\n", "string literal".ptr);
         The length comes first, followed by the pointer:)
 
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-printf("the string is '%.*s'\n", str.length, str.ptr);
+printf("the string is '%.*s'\n", cast(int)str.length, str.ptr);
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         $(P The best way is to use std.stdio.writefln, which can handle