Update client.py

[Noah-Haf]

Add group_search to client.

E.g:

 async for group in client.group_search("roblox").items(10):
    print(group.name)

Returns:

Roblox
Roblox High School: Fan Club
RODNY ROBLOX
Roblox Wiki
Studios Military Roleplay Fan Roblox Clothing
LankyBox Roblox Group!
Roblox+
Roblox Military Building Roleplaying Community
Robloxian High School Group
Roblox catalog Group fan