Bugfix: working filter by header value

[madamantis-leviathan]

When on a test, I noticed that the "Header doesn't contain" filter didn't work. It turned out that message_passed_interception_filters in authorization.py used a wrong index to get the filter value:

if interceptionFilterTitle == "Header contains":  # len = 15
            for header in list(resInfo.getHeaders()):
                if interceptionFilter[17:] in header:  # starts at (len + 2) (i.e. "Header contains: ")
                    message_passed_filters = False

        if interceptionFilterTitle == "Header doesn't contain":  # len = 22
            for header in list(resInfo.getHeaders()):
                if not interceptionFilter[17:] in header:  # the correct index would be 24 (22 + 2) 
                    message_passed_filters = False

I've fixed this using an approach where you don't have to hard-code the index. Now we split by : at the start of the function to get interceptionFilterTitle and interceptionFilterContent and cut off the extra space symbol after the filter name.

 try:
            interceptionFilterTitle, interceptionFilterContent = interceptionFilter.split(":", 1)  # split only once to avoid possible `:` in user input
            interceptionFilterContent = interceptionFilterContent[1:]  # could have been .lstrip(' '), but user input may start with a space
 except Exception as e:
            print(interceptionFilter)
            print(e)
            continue

As a bonus, I've also changed auth_enforced_via_enforcement_detectors to use the same approach. I've also expanded the filter list to distinguish between request and response headers. Here are the new filter names:

                    "Request headers contain: ",
                     "Request headers don't contain: ",
                     "Response headers contain: ",
                     "Response headers don't contain: ",

I hope this will be of use to the others. Please let me know if this needs any changes