Adding individual events to Google Calendar uses incorrect dates & encoding chars

[RCheesley]

Describe the bug

Since the latest update:

1. Exporting a single event to Google Calendar uses the wrong date/time (current rather than event)

2. Exporting a single event to Google Calendar shows the encoding chars instead of plain text for the title and description
   

3. The descriptive text with the link back to the event on Decidim is in German on all events - including those already imported via an existing calendar import:
   

To Reproduce

1. Go to an event
2. Add to calendar (bottom right)
3. Select Google Calendar
4. Notice that the date/time doesn't match the event date/time
5. Notice that instead of plain text in the title and description you're seeing text with additional unexpected characters
6. Check an existing calendar and look at the description (multilingual might be needed) - content in English but the final text is in German linking back to the event

Expected behavior

1. Correct date/time used when adding to Google Calendar
2. Plain text is correctly used in title and description
3. All text is in the same language

Screenshots

See above

Stacktrace

No response

Extra data

• Device: Macbook Pro
• Device OS: MacOS
• Browser: Chrome
• Decidim Version: 0.27.5
• Decidim installation:

Additional context

No response