Bugfix: Authorized User only gets findings through API of which he is the reporter of #2992

[Yuuichi89]

- bugfix: to #2992 latest "release/1.8.0" master

If in doubt you can use dev branch, it will just roll-out later.

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[valentijnscholten]

Good find! I did a quicks can of serializers.py yesterday, but not this file. Thanks!