remote-helper: Remove Unused Error Variants

Previous minimization of visibility modifiers enables automated
removal of these unused variants.

crates/radicle-remote-helper/src/push.rs

@@ -56,9 +56,6 @@ pub(super) enum Error {
     /// I/O error.
     #[error("i/o error: {0}")]
     Io(#[from] io::Error),
-    /// A command exited with an error code.
-    #[error("command '{0}' failed with status {1}")]
-    CommandFailed(String, i32),
     /// Invalid reference name.
     #[error("invalid ref: {0}")]
     InvalidRef(#[from] radicle::git::fmt::Error),
@@ -98,9 +95,6 @@ pub(super) enum Error {
     /// Patch is empty.
     #[error("patch commits are already included in the base branch")]
     EmptyPatch,
-    /// Missing canonical head.
-    #[error("the canonical head is missing from your working copy; please pull before pushing")]
-    MissingCanonicalHead(git::Oid),
     /// COB store error.
     #[error(transparent)]
     Cob(#[from] radicle::cob::store::Error),

crates/radicle-remote-helper/src/push/error.rs

@@ -14,8 +14,6 @@ pub(crate) enum CanonicalUnrecoverable {
     FindObjects(#[from] canonical::error::FindObjectsError),
     #[error(transparent)]
     HeadsDiverge(#[from] HeadsDiverge),
-    #[error("failure while computing canonical reference: {source}")]
-    Git { source: git::raw::Error },
 }
 
 #[derive(Debug, Error)]