fix: split headers into key value at first colon

[felixscherz]

Hi, this is in regards to #121.
With this change, headers are split into key, value pairs at the first colon.

[gorillamoe]

What a great catch 😍 !!!

[estacioneto]

Hi,

First of all, nice catch indeed, @felixscherz!

kulala.inspect() still does not show the header so running kulala.run() from the computed buffer doesn't work. I'll investigate it to see if I can find where it's failing.

FYI @gorillamoe

Edit:

It happens because the parser removes the authorization header, so the inspect function does not get it.