Add testing of report-csp-violation

Added some basic tests for both 2.x and 7.x-1.x

One difference in functionality was highlighted along the way:

    // Note: The 2.x branch returns a 404 when the submitted content-type is
    // invalid, but 7.x-1.x just quietly returns a 200.

We could change D7's _seckit_csp_report() so it would also return a 404.

I am going to call this Fixed for now though.

Automatically closed - issue fixed for 2 weeks with no activity.