Created attachment 114319 [details]
Proposed patch

Running reverse geocoding on a large set of images, generates error:
GLib-ERROR **: Creating pipes for GWakeup: Too many open files


Actions
=======
1) In the Geolocation Editor, select the Reverse Geocoding tab.
2) Select a large set of images. I used 5,000 images.
3) Select Open Street Map as the service
4) Click on Apply reverse geocding button

Expected result
===============
All images with coordinates are reversed geocoded.

Actual result
=============
After around 1,0000 requests, digikam crashes.
First I got a SSL Handshake failed, error message dialog.
Then when I exit the Editor, digikam crashes with:
GLib-ERROR **: Creating pipes for GWakeup: Too many open files

Additional info
===============
Running the same scenario again, and tracking number of open files using:
 watch -n1 "ls -la /proc/$(pidof digikam)/fd | wc -l"
I could see that the number was increasing, until I ran into the same problem.

A similar issue (https://github.com/albertlauncher/albert/issues/634) was fixed by https://github.com/albertlauncher/albert/commit/70e3662a8e3a08137073b5932dbd7ddee136ff65

When I tested their approach on digikam, digigam did not crash running the same scenario.

Given the above I propose the attached fix.