Bump secp256k1 from 0.27.0 to 0.31.0

Bumps [secp256k1](https://github.com/rust-bitcoin/rust-secp256k1) from 0.27.0 to 0.31.0.
- [Changelog](https://github.com/rust-bitcoin/rust-secp256k1/blob/master/CHANGELOG.md)
- [Commits](rust-bitcoin/rust-secp256k1@secp256k1-0.27.0...secp256k1-0.31.0)

---
updated-dependencies:
- dependency-name: secp256k1
  dependency-version: 0.31.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

Cargo.lock

@@ -7,7 +7,7 @@ const-hex = "1.14.0"
 itertools = "0.14"
 rand = {version = "^0.9", features = ["std", "std_rng"], optional = true}
 reqwest = {version = "0.12", features = ["json"], optional = true}
-secp256k1 = {version = "0.27", features = ["recovery"]}
+secp256k1 = {version = "0.31", features = ["recovery"]}
 serde = {version = "^1.0", features = ["derive"], optional = true}
 serde_json = {version = "^1.0", optional = true}
 serde_with = {version = "^3.4", features = ["hex"], optional = true}