PartialEmoji.from_str incorrectly assumes emojis starting with `a` but not including `:` are animated

[TrustyJAID]

Summary

PartialEmoji.from_str incorrectly assumes emojis starting with a but not including : are animated

Reproduction Steps

• Create an emoji that starts with a such as anemoji
• Save the emoji information as emoji_name:emoji_id, a listed valid representation for PartialEmoji.from_str.
• Call PartialEmoji.from_str("anemoji:12345678910111213")
• The returned PartialEmoji assumes that the emoji is animated when it isn't.

Minimal Reproducible Code

>>> my_emoji = PartialEmoji.from_str("anemoji:12345678910111213")
>>> print(repr(my_emoji))
>>> <PartialEmoji animated=True name='nemoji' id=12345678910111213>

Expected Results

I expected following a valid format for PartialEmoji.from_str to return a valid representation of the emoji.

Actual Results

Emojis with names starting with a are incorrectly assumed to be animated despite missing the animated separator.

Intents

all

System Information

• Python v3.11.4-final
• discord.py v2.3.0-final
• aiohttp v3.8.4
• system info: Linux 5.15.90.2-microsoft-standard-WSL2 SMP Fri Jun 2 00:45:15 UTC 2023

Checklist

• I have searched the open issues for duplicates.
• I have shown the entire traceback, if possible.
• I have removed my token from display, if visible.

Additional Context

No response