Update api_key_authentication.rst - POST Method
Check for api_key in request
feature #4128 Finished #3759 (WouterJ)

This PR was merged into the 2.4 branch.

Discussion
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Finished #3759

Finished the great start by @BourotBenjamin in #3759

Commits
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529675a Check for api_key in request
59e4bd4 Update api_key_authentication.rst - POST Method