Do not force PDFs to be downloaded (Z#23225892) (#5994)

* Display invoice and tickets inline in browser (Z#23225892)

* Use FileResponse filename for AnswerDownload

* Use inline for PDF-view in pretix-control editor

* use as_attachment for API FileResponses

* do not ignore csp even for disposition=inline

* use as_attachment for file responses in control

* remove unused code

* improve code style

* Invoice preview inline

* do not force download on tickets in backend

* do not force download on AnswerDownload

* imrpove code style

* improve code style

* fix missing int str conversion

* Apply suggestions from code review

Co-authored-by: luelista <mira@teamwiki.de>

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Co-authored-by: luelista <mira@teamwiki.de>

src/pretix/control/views/global_settings.py

@@ -300,5 +300,4 @@ class SysReportView(AdministratorPermissionRequiredMixin, TemplateView):
             resp = HttpResponse(data)
             resp['Content-Type'] = mime
             resp['Content-Disposition'] = 'inline; filename="{}"'.format(name)
-            resp._csp_ignore = True
             return resp