build(deps): bump sha2 from 0.10.7 to 0.10.8 (#163)

Bumps [sha2](https://github.com/RustCrypto/hashes) from 0.10.7 to 0.10.8.
- [Commits](RustCrypto/hashes@sha2-v0.10.7...sha2-v0.10.8)

---
updated-dependencies:
- dependency-name: sha2
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

ssh-key/Cargo.toml

@@ -19,7 +19,7 @@ rust-version = "1.65"
 [dependencies]
 cipher = { package = "ssh-cipher", version = "0.2", path = "../ssh-cipher" }
 encoding = { package = "ssh-encoding", version = "0.2", features = ["base64", "pem", "sha2"], path = "../ssh-encoding" }
-sha2 = { version = "0.10.7", default-features = false }
+sha2 = { version = "0.10.8", default-features = false }
 signature = { version = "2", default-features = false }
 subtle = { version = "2", default-features = false }
 zeroize = { version = "1", default-features = false }