Problem description: When using the "Test" option for a Webhook media type, the connection timeout value that is used during test execution is always 3 seconds and is not equal to the timeout defined in the media type itself. In this case, if the actual execution of the script takes longer than 3 seconds, the user will not be able to test the media type using this option, even if the Timeout defined in the media type is large enough for the script to complete during actual execution.

Steps to reproduce:

1. Create a webhook media type
2. For this media type specify a script that executes longer than 3 seconds and "Timeout" parameter value larger than the execution time of the script.
3. In Administration => Media types execute the Test media type option for the just created media type.

Testing the media type has timed with the following error message out even though the actual execution of the script would've been successful:

Connection timeout of 3 seconds exceeded when connecting to Zabbix server "localhost".

Expected: The timeout of media type test for webhook media types should be equal to the value defined in the media type itself.

Example: