common.py: don't error when creating embeds for users without avatars

behaviour changed in pycord 2.0:
https://docs.pycord.dev/en/stable/api/models.html#discord.User.display_avatar

fixes #467

CHANGELOG.md

@@ -5,6 +5,8 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 
 ## [Unreleased]
+### Fixed
+- Issue where embeds would not work for users without avatars (#467).
 
 
 ## [2.9.0] - 2023-01-13

common.py

@@ -167,7 +167,7 @@ def embed_factory(ctx: commands.Context) -> discord.Embed:
     """Creates an embed with neutral colour and standard footer."""
     embed = discord.Embed(timestamp=datetime.utcnow(), colour=colours.neutral)
     if ctx.author:
-        embed.set_footer(text=str(ctx.author), icon_url=str(ctx.author.avatar.url))
+        embed.set_footer(text=str(ctx.author), icon_url=str(ctx.author.display_avatar))
     return embed