fix(crypto): Remove some dead code

crates/matrix-sdk-crypto/src/backups/keys/recovery.rs

@@ -71,12 +71,6 @@ pub struct RecoveryKey {
     version: Option<String>,
 }
 
-impl RecoveryKey {
-    fn as_bytes(&self) -> &[u8] {
-        &self.key
-    }
-}
-
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct PickledRecoveryKey(String);
 

crates/matrix-sdk-crypto/src/backups/mod.rs

@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#![allow(dead_code, missing_docs)]
+#![allow(missing_docs)]
 
 use std::{
     collections::{BTreeMap, BTreeSet},