chore: drop the remaining product-code dead_code blankets (#6149)

crates/checksums/src/base64.rs

@@ -11,7 +11,6 @@
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
-#![allow(dead_code)]
 
 use base64_simd::STANDARD;
 

crates/kms/src/encryption/dek.rs

@@ -18,8 +18,6 @@
 //! data encryption keys using master keys. It abstracts the encryption
 //! operations so that different backends can share the same encryption logic.
 
-#![allow(dead_code)] // Trait methods may be used by implementations
-
 use crate::error::{KmsError, Result};
 use crate::persisted_observability::{BoundedUnknownFieldName, UnknownFieldSummary};
 use async_trait::async_trait;