Answer was to change send to send_message and to import time so I can use delta time for the duration of the poll
Fixed Code:
import time
import datetime
@client.tree.command(name="repo", description="Create a poll to see who's free for REPO", guild=GUILD_ID)
async def repo(interaction: discord.Interaction):
p = discord.Poll(question="Are you free for REPO?", duration=datetime.timedelta(hours=4))
p.add_answer(text="Yes")
p.add_answer(text="No")
await interaction.response.send_message(poll=p)