Merge rust-bitcoin#5053: Kill new mutants

9676edc Exclude encoding::Decodable from mutation testing (Jamil Lambert, PhD)

Pull request description:

  Recently added `impl encoding::Decodable` construct a new `Decoder`. Mutation testing replaces these with `Default::default()`, which is equivalent to the intended `new()`.
  
  Exclude these from mutation testing to avoid false positives.
  
  Closes rust-bitcoin#5047


ACKs for top commit:
  apoelstra:
    ACK 9676edc; successfully ran local tests


Tree-SHA512: deddca687fd91de25e586046da11242c58db8ce42f747ac9a4451a13548001c6d9e7f1d6e10f84245ac3b6fe0f23ead34762e31becb48f9a1d8e3caf915b2042

Author: apoelstra

.cargo/mutants.toml

@@ -11,6 +11,7 @@ exclude_re = [
     "deserialize", # Skip serde mutation tests
     "serde_details::<impl de::Visitor<'_>", # Skip serde mutation tests
     "Iterator", # Mutating operations in an iterator can result in an infinite loop
+    "impl encoding::Decodable", # Mutant replacing Default::default() is equivalent to returning new()
 
     # ----------------------------------Crate-specific exclusions----------------------------------
     # Units