bugfix: infinite studies paginated requests

[odeimaiz]

What do these changes do?

• Pagination: Use response._links.next
• e2e: More accurate waiting times

Related issue/s

How to test

Checklist

[codecov]

Codecov Report

Merging #2294 (5ea8753) into master (9be551a) will increase coverage by 0.0%.
The diff coverage is n/a.

@@          Coverage Diff           @@
##           master   #2294   +/-   ##
======================================
  Coverage    71.8%   71.8%           
======================================
  Files         504     504           
  Lines       19702   19702           
  Branches     1931    1931           
======================================
+ Hits        14154   14161    +7     
+ Misses       5073    5069    -4     
+ Partials      475     472    -3     

Flag	Coverage Δ
integrationtests	62.0% <ø> (+<0.1%)	⬆️
unittests	67.1% <ø> (-0.1%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
...ce_webserver/resource_manager/garbage_collector.py	75.7% <0.0%> (+0.9%)	⬆️
...webserver/computation_comp_tasks_listening_task.py	88.1% <0.0%> (+5.3%)	⬆️