Address some ruff smells.

cogs/commands/hi.py

@@ -1,29 +1,22 @@
-"""
-Example command file.
-"""
+"""Example command file."""
 
 import nextcord
 from nextcord.ext import commands
 
 
 class HiCog(commands.Cog, name="Test commands."):
-    """
-    Class holds commands for testing.
-    """
+    """Class holds commands for testing."""
 
-    def __init__(self, bot) -> None:
-        """
-        Default constructor for HelpCog class. Does nothing.
-        """
+    def __init__(self, bot: nextcord.Bot) -> None:
         self.bot = bot
 
     @nextcord.slash_command()
-    async def hi(self, interaction: nextcord.Interaction):
+    async def hi(self, interaction: nextcord.Interaction) -> None:
         """
-        Says hi
+        Says hi.
 
         Args:
             interaction (nextcord.Interaction): Interaction to reply to.
-        """
 
+        """
         await interaction.response.send_message("Hi!", ephemeral=True)