Merge rust-bitcoin/rust-miniscript#846: Invert malleability test in best_tap_spend

36349ba51bd4ae3f51cd3b4768e024da0a376935 Invert malleability test in `best_tap_spend` (Daniel Roberts)

Pull request description:

  I *really* don't feel like I have enough context to be confident in this change, but at the same time this seems pretty obviously backwards to the best of my (currently lacking) knowledge.


ACKs for top commit:
  apoelstra:
    ACK 36349ba51bd4ae3f51cd3b4768e024da0a376935; successfully ran local tests


Tree-SHA512: 036a1d284f4014ff1c14b88685d148091d36ada5a6ce64dd552f0df26e762dc1f393a3436d0940d69ac68864c1f3f906a6f03a6a6b7b0ae2387e7a3d2ea29aaf

Author: heap-coder

src/descriptor/tr/mod.rs

@@ -488,12 +488,12 @@ where
         let mut min_wit_len = None;
         for leaf in spend_info.leaves() {
             let mut satisfaction = if allow_mall {
-                match leaf.miniscript().build_template(provider) {
+                match leaf.miniscript().build_template_mall(provider) {
                     s @ Satisfaction { stack: Witness::Stack(_), .. } => s,
                     _ => continue, // No witness for this script in tr descriptor, look for next one
                 }
             } else {
-                match leaf.miniscript().build_template_mall(provider) {
+                match leaf.miniscript().build_template(provider) {
                     s @ Satisfaction { stack: Witness::Stack(_), .. } => s,
                     _ => continue, // No witness for this script in tr descriptor, look for next one
                 }