Wrong actor ID is used when creating a note linked to an episode

Describe the bug

When you create a note that is linked to an episode, the wrong actor id is used (probably the podcast id instead of the actor id)

Steps to reproduce

1. Empty database, install castopod from scratch
2. Before creating a podcast, run ALTER TABLE cp_podcasts AUTO_INCREMENT=2; on mysql
3. Create a podcast from Castopod admin panel (podcast id = 2, podcast actor id = 1)
4. Follow that podcast from a remote Mastodon server (follower actor id = 2)
5. Create an episode from Castopod admin panel
6. Create a note for that episode

Expected behavior

Note should be created by the podcast actor.

Actual behavior

Note is created by actor whose id is 2 instead on 1.

Relevant logs and/or screenshots

Context

• Castopod: alpha-49
• OS: any
• Browser: any
• Web server: any

Possible fixes

Use the correct id. ;-)