fix emoji.edit allowing roleslist

[Donbur4156]

Pull Request Type

• Feature addition
• Bugfix
• Documentation update
• Code refactor
• Tests improvement
• CI/CD pipeline enhancement
• Other: [Replace with a description]

Description

Allowing list of Roles in CustomEmoji.edit() by converting it to snowflake_list.

Changes

add to_snowflake_list() to convert list of Roles into list of snowflakes, according the roles argument definition.

Related Issues

#1426

Test Scenarios

role1, role2 = interactions.Role(...)
emoji = await guild.fetch_custom_emoji(emoji_id=emoji_id)
await emoji.edit(roles=[role1, role2])

Python Compatibility

• I've ensured my code works on Python 3.10.x
• I've ensured my code works on Python 3.11.x

Checklist

• I've run the pre-commit code linter over all edited files
• I've tested my changes on supported Python versions
• I've added tests for my code, if applicable
• I've updated / added documentation, where applicable