Read receipts are deactivated for both if one chat user has it deactivated

[matthesatox]

Describe the bug
Read receipts are deactivated for both if one chat user has it deactivated

To Reproduce
Occurrence: always
Steps to reproduce the behavior:

1. Create or use a chat with 2 participants
2. User A sends a message to user B and vice versa
3. Check the read receipt for both messages. It should be visible for both
4. User A goes to settings --> General settings --> Chat
5. Deactivate option for sending read receipt
6. User B sends a message to user A
7. User B doesn't get a read receipt
8. User A sends a message to user B
9. User A doesn't also get a read receipt

Expected behavior
The read receipt shouldn't only be send for the user, who has deactivated the option for sending it.

Screenshots
If applicable, add screenshots to help explain your problem.

App information (please complete the following information):

• App version: [e.g. 0.4.0]
• Plugin version: [e.g. 0.4.0]
• Delta Chat Core version: [e.g. 0.40.0]
• Flutter version: [e.g. 1.0]

Smartphone (please complete the following information):

• Device: iPhone 11 Pro Max
• OS: iOS 13.5

Additional context
Add any other context about the problem here.

Internal Bug Tracker.

[Boehrsi]

I think we can't really do something about this as the DCC (https://c.delta.chat/classdc__context__t.html#aff3b894f6cfca46cab5248fdffdf083d) only allows to mdns_enabled = 0=do not send or request read receipts, 1=send and request read receipts (default) so enable / disable send and request together.