fix: Fix crawler deadlock when API fails during marking request as handled

[Pijukatel]

Description

• Fix a rare scenario where RequestQueue is in an invalid state due to a failed API call to mark the request as handled. This invalid state can lead to a crawler deadlock.
• Fixed only for ApifyRequestQueueSingleClient, as for the shared client, it is not possible to distinguish between API failure and external modification of the queue on the platform.

Issues

• Partially fixes: Fix rare case when crawler can get deadlocked

Testing

• Added unit test

Checklist

• CI passed

[codecov]

Codecov Report

❌ Patch coverage is 88.88889% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 81.98%. Comparing base (a814c63) to head (b6f5284).
⚠️ Report is 3 commits behind head on master.

Files with missing lines	Patch %	Lines
...age_clients/_apify/_request_queue_shared_client.py	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #768      +/-   ##
==========================================
+ Coverage   81.86%   81.98%   +0.12%     
==========================================
  Files          46       46              
  Lines        2696     2698       +2     
==========================================
+ Hits         2207     2212       +5     
+ Misses        489      486       -3     

Flag	Coverage Δ
e2e	43.47% <0.00%> (-0.04%)	⬇️
integration	55.67% <88.88%> (+0.21%)	⬆️
unit	67.90% <0.00%> (-0.13%)	⬇️

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

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[vdusek]

One potential misleading docstring. Otherwise, LGTM.