When an episode is scheduled on a new season, cache is not completly updated

Describe the bug

When an episode is scheduled on a new season, most recent season is not updated.

Steps to reproduce

1. create episode s01e01, publish it
2. create episode s02ep01, schedule it
3. wait until scheduled episode is published
4. go to podcast homepage: it will show season 1 instead of season 2.
5. empty cache
6. go to podcast homepage: it will show season 2.

Expected behavior

Most recent season should be displayed.

Actual behavior

Previous season is displayed.

Relevant logs and/or screenshots

Context

• Castopod: alpha 18
• OS: cloud panel
• Browser: any
• Web server: nginx