feat: allow emojis to be set by environment variables

[vcokltfre]

Adds the ability to set custom emoji as environment variables:

• EMOJI_CHECK
• EMOJI_ERROR
• EMOJI_BAN
• EMOJI_UNBAN
• EMOJI_NOTE
• EMOJI_WARN
• EMOJI_KICK
• EMOJI_MUTE
• EMOJI_UNMUTE
• EMOJI_CASE_DELETED
• EMOJI_SOFTBAN

[almeidx]

The bot.env.example file should be updated

[ghost]

The errorMessage() function's emoji should be configurable as well.

[vcokltfre]

I feel like I should add a note somewhere saying that you dont actually need the emoji env vars to run the bot, and during development you should probably just remove them, but I'm not sure where to put that. Should I add a note in the bot.env.example file or in the readme, or somewhere else?

[almeidx]

A comment in the env example file should be sufficient

[Dragory]

I think these would be a better fit for the global config, or even individual guild configs. In fact, guild configs already include the fields success_emoji and error_emoji.

[vcokltfre]

Ah that's out of my abilities so I'll let someone else do that lol