Deprecate is_allowed_by_hierarchy() core util (#4435)

redbot/cogs/mod/utils.py

@@ -0,0 +1,13 @@
+import discord
+
+from redbot.core.bot import Red
+from redbot.core.config import Config
+
+
+async def is_allowed_by_hierarchy(
+    bot: Red, config: Config, guild: discord.Guild, mod: discord.Member, user: discord.Member
+):
+    if not await config.guild(guild).respect_hierarchy():
+        return True
+    is_special = mod == guild.owner or await bot.is_owner(mod)
+    return mod.top_role.position > user.top_role.position or is_special