fix: Use qualified endpoints for updating conversation properties [WPB-4492]

[atomrc]

WPB-4492 [Web] cannot set notification status on a conversation owned by a different backend

Description

This will make sure that the following actions are possible on remote federated conversations:

• update notification preferences
• change timer setting
• archive

see wireapp/wire-web-packages#5467

Checklist

• PR has been self reviewed by the author;
• Hard-to-understand areas of the code have been commented;
• If it is a core feature, unit tests have been added;

[codecov]

Codecov Report

Merging #15751 (97219bb) into dev (caae58e) will decrease coverage by 0.03%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##              dev   #15751      +/-   ##
==========================================
- Coverage   44.50%   44.48%   -0.03%     
==========================================
  Files         672      672              
  Lines       22703    22703              
  Branches     5167     5167              
==========================================
- Hits        10105    10100       -5     
- Misses      11310    11314       +4     
- Partials     1288     1289       +1