Add event to track Podcasts list discover button tap

[mebarbosa]

Description

• Just adds the missing event track for Discover Podcasts button
• Context: p1734591702871389-slack-C029BMLUGRX

Testing Instructions

1. Start the app from scratch
2. Go to Podcasts tab
3. You should screen the screen above
4. Tap on the Discover Podcasts
5. ✅ Ensure the podcasts_list_discover_button_tapped event is tracked

Screenshots or Screencast

Checklist

• If this is a user-facing change, I have added an entry in CHANGELOG.md
• Ensure the linter passes (./gradlew spotlessApply to automatically apply formatting/linting)
• I have considered whether it makes sense to add tests for my changes
• All strings that need to be localized are in modules/services/localization/src/main/res/values/strings.xml
• Any jetpack compose components I added or changed are covered by compose previews
• I have updated (or requested that someone edit) the spreadsheet to reflect any new or changed analytics.

[dangermattic]

	1 Warning
⚠️	This PR is assigned to the milestone 7.80. The due date for this milestone has already passed. Please assign it to a milestone with a later deadline or check whether the release for this milestone has already been finished.

Generated by 🚫 Danger

[wpmobilebot]

📲 You can test the changes from this Pull Request in 📱 Mobile by scanning the QR code below to install the corresponding build.

	App Name	📱 Mobile
	Build Type	debugProd
	Commit	4d14f8e
	Direct Download	pocketcasts-app-prototype-build-pr3396-4d14f8e.apk

📲 You can test the changes from this Pull Request in 🚗 Automotive by scanning the QR code below to install the corresponding build.

	App Name	🚗 Automotive
	Build Type	debugProd
	Commit	4d14f8e
	Direct Download	pocketcasts-automotive-prototype-build-pr3396-4d14f8e.apk

📲 You can test the changes from this Pull Request in ⌚ Wear by scanning the QR code below to install the corresponding build.

	App Name	⌚ Wear
	Build Type	debugProd
	Commit	4d14f8e
	Direct Download	pocketcasts-wear-prototype-build-pr3396-4d14f8e.apk