Remove deprecated Member and Guild methods (serenity-rs#2817)

Followup to serenity-rs#2816

---------

Co-authored-by: Alex M. M. <acdenissk69@gmail.com>

src/model/guild/member.rs

@@ -260,24 +260,6 @@ impl Member {
         Ok(())
     }
 
-    /// Retrieves the ID and position of the member's highest role in the hierarchy, if they have
-    /// one.
-    ///
-    /// This _may_ return [`None`] if the user has roles, but they are not present in the cache for
-    /// cache inconsistency reasons.
-    ///
-    /// The "highest role in hierarchy" is defined as the role with the highest position. If two or
-    /// more roles have the same highest position, then the role with the lowest ID is the highest.
-    #[cfg(feature = "cache")]
-    #[deprecated = "Use Guild::member_highest_role"]
-    pub fn highest_role_info(&self, cache: &Cache) -> Option<(RoleId, i16)> {
-        cache
-            .guild(self.guild_id)
-            .as_ref()
-            .and_then(|g| g.member_highest_role(self))
-            .map(|r| (r.id, r.position))
-    }
-
     /// Kick the member from the guild.
     ///
     /// **Note**: Requires the [Kick Members] permission.

src/model/guild/mod.rs

@@ -362,7 +362,7 @@ impl Guild {
     fn check_hierarchy(&self, cache: &Cache, other_user: UserId) -> Result<()> {
         let current_id = cache.current_user().id;
 
-        if let Some(higher) = self.greater_member_hierarchy(cache, other_user, current_id) {
+        if let Some(higher) = self.greater_member_hierarchy(other_user, current_id) {
             if higher != current_id {
                 return Err(Error::Model(ModelError::Hierarchy));
             }
@@ -1302,13 +1302,8 @@ impl Guild {
     /// owner, their ID is returned.
     ///
     /// [`position`]: Role::position
-    #[cfg(feature = "cache")]
-    pub fn greater_member_hierarchy(
-        &self,
-        #[allow(unused_variables)] cache: &Cache,
-        lhs_id: UserId,
-        rhs_id: UserId,
-    ) -> Option<UserId> {
+    #[must_use]
+    pub fn greater_member_hierarchy(&self, lhs_id: UserId, rhs_id: UserId) -> Option<UserId> {
         // Check that the IDs are the same. If they are, neither is greater.
         if lhs_id == rhs_id {
             return None;

src/model/guild/partial_guild.rs

@@ -15,8 +15,6 @@ use crate::builder::{
     EditRole,
     EditSticker,
 };
-#[cfg(all(feature = "cache", feature = "utils", feature = "client"))]
-use crate::cache::Cache;
 #[cfg(feature = "collector")]
 use crate::collector::{MessageCollector, ReactionCollector};
 #[cfg(feature = "collector")]
@@ -898,30 +896,6 @@ impl PartialGuild {
         guild_id.to_partial_guild(cache_http).await
     }
 
-    /// Returns which of two [`User`]s has a higher [`Member`] hierarchy.
-    ///
-    /// Hierarchy is essentially who has the [`Role`] with the highest [`position`].
-    ///
-    /// Returns [`None`] if at least one of the given users' member instances is not present.
-    /// Returns [`None`] if the users have the same hierarchy, as neither are greater than the
-    /// other.
-    ///
-    /// If both user IDs are the same, [`None`] is returned. If one of the users is the guild
-    /// owner, their ID is returned.
-    ///
-    /// [`position`]: Role::position
-    #[cfg(feature = "cache")]
-    #[deprecated = "Use Cache::guild and Guild::greater_member_hierarchy"]
-    pub fn greater_member_hierarchy(
-        &self,
-        cache: &Cache,
-        lhs_id: UserId,
-        rhs_id: UserId,
-    ) -> Option<UserId> {
-        let guild = cache.guild(self.id)?;
-        guild.greater_member_hierarchy(cache, lhs_id, rhs_id)
-    }
-
     /// Calculate a [`Member`]'s permissions in the guild.
     #[cfg(feature = "cache")]
     #[must_use]