fix: simplify mime-type checks to support jpg and other image formats

[Koc]

This PR should fix #2399

TODO:

• deeper manual testing
• check tests failures

[codecov]

Codecov Report

Attention: Patch coverage is 42.85714% with 4 lines in your changes missing coverage. Please review.

Please upload report for BASE (main@39bd5df). Learn more about missing BASE report.
Report is 75 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2401   +/-   ##
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  Coverage        ?   42.86%           
  Complexity      ?      854           
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  Files           ?       72           
  Lines           ?     3201           
  Branches        ?        0           
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  Hits            ?     1372           
  Misses          ?     1829           
  Partials        ?        0           

[Chartman123]

/backport to stable4

[Chartman123]

@Koc I think we need some adjustments in the backport as we have the duplicated endpoints there.

[Koc]

I've re-tested it one more time:

Created a form with file question type. Allowed images + pdf.

1. png - uploaded
2. jpg - uploaded
3. pdf - uploaded
4. sql - not uploaded
5. zip - not uploaded

@Chartman123 I can backport changes manualy once we merged this one.

Let's merge?

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