Cargo: avoid unused aws-lc-rs default features

The aws-lc-rs crate defaults to enabling the `ring-io` and
`ring-sig-verify` features, but we use neither in this crate. Avoiding
these features is beneficial because it prevents the inclusion of
a second copy of `untrusted` in the dependency tree.

Cargo.toml

@@ -79,7 +79,7 @@ ring = ["dep:ring"]
 std = ["alloc", "pki-types/std"]
 
 [dependencies]
-aws-lc-rs = { version = "1.0.0", optional = true }
+aws-lc-rs = { version = "1", optional = true, default-features = false, features = ["aws-lc-sys"] }
 pki-types = { package = "rustls-pki-types", version = "1", default-features = false }
 ring = { version = "0.17", default-features = false, optional = true }
 untrusted = "0.9"