Rust 1.54.0 lints (#2483)

## Issue Addressed

N/A

## Proposed Changes

- Removing a bunch of unnecessary references
- Updated `Error::VariantError` to `Error::Variant`
- There were additional enum variant lints that I ignored, because I thought our variant names were fine
- removed `MonitoredValidator`'s `pubkey` field, because I couldn't find it used anywhere. It looks like we just use the string version of the pubkey (the `id` field) if there is no index

## Additional Info



Co-authored-by: realbigsean <seananderson33@gmail.com>

crypto/bls/src/impls/blst.rs

@@ -132,7 +132,7 @@ impl TPublicKey for blst_core::PublicKey {
                 expected: PUBLIC_KEY_BYTES_LEN,
             });
         }
-        Self::key_validate(&bytes).map_err(Into::into)
+        Self::key_validate(bytes).map_err(Into::into)
     }
 }
 
@@ -278,6 +278,6 @@ impl TSecretKey<blst_core::Signature, blst_core::PublicKey> for blst_core::Secre
     }
 
     fn deserialize(bytes: &[u8]) -> Result<Self, Error> {
-        Self::from_bytes(&bytes).map_err(Into::into)
+        Self::from_bytes(bytes).map_err(Into::into)
     }
 }