88a79cb436b30b39d37d139da723f5a31e9d161b fix converttopsbt permitsigdata arg, add basic test (Gregory Sanders)
Pull request description:
The final check for extraneous sigdata has a flipped boolean, resulting in incorrect behavior.
Resolves https://github.com/bitcoin/bitcoin/issues/14355
Tree-SHA512: 5157a74b8ddebd7d836fba96765c4d7ed15a73d4289817353d3566a0f6803bd4bbc3f936735c517c7a83a6cbdb4052b9c61d23f6cc4ad00a6077278cd51adbd4