keymgr: Remove outdated TODOs regarding error handling.

These were tackled in #901.

crates/tor-keymgr/src/err.rs

@@ -11,8 +11,6 @@ use std::fmt;
 pub type Error = Box<dyn KeystoreError>;
 
 /// An error returned by a [`KeyStore`](crate::KeyStore).
-// TODO hs: replace Error with KeyStoreError and create an `ArtiNativeKeyStoreError: KeyStoreError`
-// type for ArtiNativeKeyStore.
 pub trait KeystoreError:
     HasKind + StdError + DynClone + fmt::Debug + fmt::Display + Send + Sync + 'static
 {

crates/tor-keymgr/src/key_type/ssh.rs

@@ -41,8 +41,6 @@ impl UnparsedOpenSshKey {
 }
 
 /// An error that occurred while processing an OpenSSH key.
-//
-// TODO hs: use this error type instead of crate::Error.
 #[derive(thiserror::Error, Debug, Clone)]
 pub(crate) enum SshKeyError {
     /// Failed to parse an OpenSSH key