Fix bug on typing for some commands not stopping when message sent

[itzmk21]

discordpy docs gave this example of usage:

async with channel.typing():
    # do expensive stuff here
    await channel.send('done!')

While nextcord docs gave this:

async with channel.typing():
    # simulate something heavy
    await asyncio.sleep(10)

await channel.send('done!')

Basically

async with channel.typing():
   # expensive stuff
-  await channel.send('done!')
+await channel.send('done!')

Feel like the update in the nextcord docs shows there was an error in the discordpy docs itself, and with tests, the "endless" typing should be fixed, now.