Event rotation, bug fixes, removing prevent_ratelimit and get_constants, and dropping Python <3.8 support

[4.2.0] - 10/8/24

Added

• Implemented an endpoint with Client.get_event_rotation which gets the events in the current rotation.
• Added a method Player.get_battle_logs which directly gets the player's battle log.

Fixed

• Client actually uses session passed into parameters now instead of creating a new one anyways
• UnexpectedError now properly shows the returned text in the message
• The use_cache parameter now works for get_brawlers and the async client

Removed

• Removed the prevent_ratelimit option for the Client
• Dropped support for Python 3.5, 3.6, 3.7, and 3.8
• Removed Client.get_constants as the site that was hosting it is no longer running