Missing common image mimetypes from file upload restricted for image type

[gyuris]

Describe the bug Currently (Forms 4.3.2) for file upload=image only allows these mimetypes: application/coreldraw application/illustrator application/postscript application/x-dcraw application/x-gimp application/x-photoshop

To Reproduce Steps to reproduce the behavior:

1. Go to Forms
2. Create a new form
3. Add a field type file
4. Restrict allowed types to image
5. See it in action: you can not add a simple jpg file

Expected behavior I expect for example to be allowed these types: image/apng image/gif image/jpeg image/png image/svg+xml

Nextcloud (please complete the following information):

• Nextcloud-Version: Nextcloud Hub 8 (29.0.8)
• Forms-Version: Forms 4.3.2

Desktop (please complete the following information):

• OS: Windows
• Browser: Chrome and Firefox
• Version: Ch-130, F-132

[Chartman123]

@Koc could you please have a look at this issue?

[Koc]

Indeed, not everything clear here. I've opened draft PR to fix that, see #2401