[fix] Unable to add invitees to calendar event / unable to accept calendar event invites

## Describe the bug

**Node.js version:** N/A

**OS version:** macOS and iOS

**Description:** Three possibly related issues for invitees on calendar events, confirmed in Calendar on macOS or iOS.
1. When invited to an event from another email address, the invite does not show up in the calendar app inbox.
2. It isn't possible to respond to event invitations
3. It isn't possible to add event attendees to events created in Calendar

## Actual behavior

**Receiving invites:**
1. Send a calendar invite from an alias (I used gmail) to a forward email alias
2. You'll receive an email but nothing in the calendar inbox:

**Responding to invites:**
1. Send a calendar invite from an alias (I used gmail) to a forward email alias
2. Download .ics from email notification for event invite and add it to macOS Calendar
3. There's no option to respond with going / maybe / can't go

**Sending invites:**

Event has no invitees field:

This isn't the case in Thunderbird; it is possible to add attendees to events in that calendar client.

## Expected behavior

**Receiving invites:**
1. Send a calendar invite from an alias to any non-forward email alias
2. You'll receive an email and an invite in the calendar inbox:

It should work this way for invites send to forward email aliases

**Responding to invites:**

You should be able to respond to events:

**Sending invites:**

Looks like this with an invitees field:

## Code to reproduce

N/A

## Checklist

- [x] I have searched through GitHub issues for similar issues.
- [x] I have completely read through the README and documentation.
- [N/A] I have tested my code with the latest version of Node.js and this package and confirmed it is still not working.