Bump config from 0.9.3 to 0.10.1

Bumps [config](https://github.com/mehcode/config-rs) from 0.9.3 to 0.10.1.
- [Release notes](https://github.com/mehcode/config-rs/releases)
- [Changelog](https://github.com/mehcode/config-rs/blob/master/CHANGELOG.md)
- [Commits](https://github.com/mehcode/config-rs/commits)

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

Author: dependabot-preview[bot]

Cargo.lock

@@ -15,7 +15,7 @@ bitcoin = { version = "0.19.1", features = ["use-serde"] }
 blockchain_contracts = "0.1"
 byteorder = "1.3"
 chrono = { version = "0.4", features = ["serde"] }
-config = { version = "0.9", features = ["toml"] }
+config = { version = "0.10", features = ["toml"] }
 debug_stub_derive = "0.3"
 derivative = "1"
 derive_more = "0.99.2"