Fix a trivial genconfig warning
Fix a trivial genconfig warning

Add missing "allowed key" for metadata to avoid an unnecessary warning.

jmptrader/duktape,markand/duktape,svaarala/duktape,jmptrader/duktape,harold-b/duktape,jmptrader/duktape,jmptrader/duktape,harold-b/duktape,markand/duktape,jmptrader/duktape,svaarala/duktape,svaarala/duktape,svaarala/duktape,markand/duktape,harold-b/duktape,jmptrader/duktape,jmptrader/duktape,svaarala/duktape,markand/duktape,markand/duktape,harold-b/duktape,svaarala/duktape,harold-b/duktape,harold-b/duktape,svaarala/duktape,harold-b/duktape,svaarala/duktape,svaarala/duktape,markand/duktape,markand/duktape,harold-b/duktape,jmptrader/duktape,markand/duktape,markand/duktape,jmptrader/duktape,harold-b/duktape,jmptrader/duktape,markand/duktape,harold-b/duktape