Bug 489207

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SUMMARY
One can't open images larger than 2000 megabytes like the full size hubble images even though images aren't on or larger than 2000MB

STEPS TO REPRODUCE
1. Download one of the large images of https://hubblesite.org/contents/media/images/2019/17/4492-Image.html
    - This can be the full size png https://stsci-opo.org/STScI-01EVSVZXR09GBZKNZ8PRN288G2.png
    - Or the tiff, doesn't really matter https://stsci-opo.org/STScI-01EVSW40QY4W0GC78APRTRYYBC.tif
2. Try to open it with gwenview.
3. It won't display but shows a "Loading image failed" message.

OBSERVED RESULT
Image doesn't load or view at all. Application doesn't give reason but the log does. Given journalctl log entries;
```
jun 26 01:21:37 hostname systemd[914]: Started Gwenview - Image Viewer.
jun 26 01:21:37 hostname gwenview[25322]: Qt: Session management error: None of the authentication protocols specified are supported
jun 26 01:21:37 hostname gwenview[25322]: kf.i18n.kuit: "Unknown subcue ':whatsthis,' in UI marker in context {@info:whatsthis, %1 the action's text}."
jun 26 01:21:37 hostname gwenview[25322]: org.kde.kdegraphics.gwenview.lib: Unresolved mime type  "image/x-mng"
jun 26 01:21:37 hostname gwenview[25322]: org.kde.kdegraphics.gwenview.lib: Unresolved raw mime type  "image/x-samsung-srw"
jun 26 01:21:38 hostname gwenview[25322]: qt.gui.imageio: QImageIOHandler: Rejecting image as it exceeds the current allocation limit of 2000 megabytes
jun 26 01:21:39 hostname gwenview[25322]: qt.gui.imageio: QImageIOHandler: Rejecting image as it exceeds the current allocation limit of 2000 megabytes
jun 26 01:21:39 hostname gwenview[25322]: qt.gui.imageio: QImageIOHandler: Rejecting image as it exceeds the current allocation limit of 2000 megabytes
jun 26 01:21:45 hostname systemd[914]: app-org.kde.gwenview-c44d0b1477a944c186b26d8c6c294db3.scope: Consumed 1.923s CPU time.
```

EXPECTED RESULT
Expected the image to load & be viewable. Especially since the given images aren't on or over 2000 MB.


SOFTWARE/OS VERSIONS
Windows: Untested
macOS: Untested
Linux/KDE Plasma:  Manjaro Linux 24.0.2 Wynsdey x86_64
(available in About System)
KDE Plasma Version: 6.0.5 (x11)
KDE Frameworks Version: 5.116.0
Qt Version: 5.15.14

ADDITIONAL INFORMATION