Update secp256k1 requirement from 0.20.2 to 0.25.0

Updates the requirements on [secp256k1](https://github.com/rust-bitcoin/rust-secp256k1) to permit the latest version.
- [Release notes](https://github.com/rust-bitcoin/rust-secp256k1/releases)
- [Changelog](https://github.com/rust-bitcoin/rust-secp256k1/blob/master/CHANGELOG.md)
- [Commits](https://github.com/rust-bitcoin/rust-secp256k1/commits/secp256k1-0.25.0)

---
updated-dependencies:
- dependency-name: secp256k1
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

lightning-invoice/Cargo.toml

@@ -20,7 +20,7 @@ std = ["bitcoin_hashes/std", "num-traits/std", "lightning/std", "bech32/std"]
 [dependencies]
 bech32 = { version = "0.8", default-features = false }
 lightning = { version = "0.0.105", path = "../lightning", default-features = false }
-secp256k1 = { version = "0.20", default-features = false, features = ["recovery", "alloc"] }
+secp256k1 = { version = "0.25", default-features = false, features = ["recovery", "alloc"] }
 num-traits = { version = "0.2.8", default-features = false }
 bitcoin_hashes = { version = "0.10", default-features = false }
 hashbrown = { version = "0.11", optional = true }

lightning/Cargo.toml

@@ -37,7 +37,7 @@ default = ["std"]
 [dependencies]
 bitcoin = { version = "0.27", default-features = false, features = ["secp-recovery"] }
 # TODO remove this once rust-bitcoin PR #637 is released
-secp256k1 = { version = "0.20.2", default-features = false, features = ["alloc"] }
+secp256k1 = { version = "0.25.0", default-features = false, features = ["alloc"] }
 
 hashbrown = { version = "0.11", optional = true }
 hex = { version = "0.4", optional = true }
@@ -50,7 +50,7 @@ core2 = { version = "0.3.0", optional = true, default-features = false }
 hex = "0.4"
 regex = "0.2.11"
 # TODO remove this once rust-bitcoin PR #637 is released
-secp256k1 = { version = "0.20.2", default-features = false, features = ["alloc"] }
+secp256k1 = { version = "0.25.0", default-features = false, features = ["alloc"] }
 
 [dev-dependencies.bitcoin]
 version = "0.27"