Move podcastShared analytics events

[bjtitus]

This handles the early returns added in #2582 so we don't log a podcastShared event when private podcasts are shared.

To test

Private Podcast

• Enable the tracksLogging feature flag

• Open the Podcast detail screen for a private podcast

• Tap "Share" and verify that only the following event is logged with no podcast_shared event:

🔵 Tracked: podcast_screen_share_tapped

• Open the episode detail page

• Verify that no event is logged when tapping share

• Play an episode from this podcast

• Open the player

• Tap the "Share" action button in the shelf

• Verify that no podcast_shared event is logged

Public Podcast

• For a public podcast, do the following:
• Open the Podcast detail page
• Tap Share and see the following logged:

🔵 Tracked: podcast_shared ["type": "podcast", "source": "podcast_screen"]

• Open the Episode detail page
• Tap Share and select the options and you should see the following logged with the "type" swapped out as above:

🔵 Tracked: podcast_shared ["source": "episode_detail", "type": "episode"]

• Open the player
• Tap the "Share" action button in the shelf
• Select one of the options from the menu and you should see the following logged for each corresponding option:

🔵 Tracked: podcast_shared ["type": "episode", "source": "player"]
🔵 Tracked: podcast_shared ["type": "podcast", "source": "player"]
🔵 Tracked: podcast_shared ["type": "current_position", "source": "player"]
🔵 Tracked: podcast_shared ["type": "clip", "source": "player"]

Checklist

• I have considered if this change warrants user-facing release notes and have added them to CHANGELOG.md if necessary.
• I have considered adding unit tests for my changes.
• I have updated (or requested that someone edit) the spreadsheet to reflect any new or changed analytics.