not getting all request headers

[jeremyandrews]

Goose is able to collect custom headers sent during a request, but doesn't get the default headers configured in the Client object.

For this reason, Goose only seems to log request headers added specifically for POST requests. Somehow we need to also see all the headers maintained/set by the Client object, but this doesn't seem to be exposed by reqwest.

[jeremyandrews]

Relevant upstream issues:

• No place to get "actual" header that has been sent seanmonstar/reqwest#264 (this one proposes an upstream resolution)
• Ability to see automatically added headers seanmonstar/reqwest#314
• Calling Request.headers() does not return automatically-inserted or default headers. seanmonstar/reqwest#788
• Access Request headers set by library before or after sending request seanmonstar/reqwest#1229