Merge #634: fuzz: cover taproot in roundtrip_miniscript_str

3b47c3c fuzz: cover taproot in `roundtrip_miniscript_str` (Bruno Garcia)

Pull request description:

ACKs for top commit:
  apoelstra:
    ACK 3b47c3c

Tree-SHA512: 2f99117f937f2658cf620b5ed1348d45c16e62bb0aab40a2e0955c90c5efd8bd674a275095e058717f11f448e1c2ff578324af4d321d08cf17eaf3ef8bc5c2b9

fuzz/fuzz_targets/roundtrip_miniscript_str.rs

@@ -1,14 +1,19 @@
 use std::str::FromStr;
 
 use honggfuzz::fuzz;
-use miniscript::{Miniscript, Segwitv0};
+use miniscript::{Miniscript, Segwitv0, Tap};
 
 fn do_test(data: &[u8]) {
     let s = String::from_utf8_lossy(data);
     if let Ok(desc) = Miniscript::<String, Segwitv0>::from_str(&s) {
         let str2 = desc.to_string();
         let desc2 = Miniscript::<String, Segwitv0>::from_str(&str2).unwrap();
 
+        assert_eq!(desc, desc2);
+    } else if let Ok(desc) = Miniscript::<String, Tap>::from_str(&s) {
+        let str2 = desc.to_string();
+        let desc2: Miniscript<String, Tap> = Miniscript::<String, Tap>::from_str(&str2).unwrap();
+
         assert_eq!(desc, desc2);
     }
 }