Update cargo mutants to version 25.3.1

Author: benalleng

.github/workflows/rust.yml

@@ -141,7 +141,7 @@ jobs:
           git diff origin/${{ github.base_ref }}.. | tee git.diff
       - uses: taiki-e/install-action@v2
         with:
-          tool: cargo-mutants@25.2.2
+          tool: cargo-mutants@25.3.1
       - name: "Install toolchain"
         uses: dtolnay/rust-toolchain@stable
       - name: "Use cache"