Force Content-type header to application/json if is_pre740 is false (#10832)
* Force Content-type header to application/json if is_pre740 is false
* Remove response variable from fail_json module
* Add a missing blank line to match pep8 requirement
* Add changelog fragment of issue #10796
* Rename fragment section
* Improve fragment readability
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(cherry picked from commit 0f23b9e391)
Co-authored-by: X <2465124+broferek@users.noreply.github.com>
Co-authored-by: ludovic <ludovic.petetin@aleph-networks.com>
Co-authored-by: Felix Fontein <felix@fontein.de>
01d0f3ccb7