Add audit job in CI workflow

.github/workflows/rust.yml

@@ -53,3 +53,9 @@ jobs:
       - uses: Swatinem/rust-cache@v2
       - run: cargo fmt --all -- --check
       - run: cargo clippy --all-targets -- -D warnings
+
+  Audit:
+    runs-on: ubuntu-22.04
+    steps:
+    - uses: actions/checkout@v4
+    - uses: EmbarkStudios/cargo-deny-action@v1

deny.toml

@@ -0,0 +1,10 @@
+[licenses]
+allow-osi-fsf-free = "either"
+copyleft = "warn"
+exceptions = [{ allow = ["ISC", "MIT", "OpenSSL"], name = "ring" }]
+private = { ignore = true }
+
+[[licenses.clarify]]
+name = "ring"
+expression = "ISC AND MIT AND OpenSSL"
+license-files = [{ path = "LICENSE", hash = 0xbd0eed23 }]