only add body if verb is not head

[DyfanJones]

Ensure head has empty body. This ensure head isn't turn off by post.

curl options:

• post: httr2:::req_body_apply_raw which adds CURLOPT_POST:

When setting CURLOPT_POST to 1, libcurl automatically sets CURLOPT_NOBODY and CURLOPT_HTTPGET to 0

• nobody: httr2:::req_method_apply which adds CURLOPT_NOBODY:

A long parameter set to 1 tells libcurl to not include the body-part in the output when doing what would otherwise be a download. For HTTP(S), this makes libcurl do a HEAD request

Fixes: #868

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 83.20%. Comparing base (91ac751) to head (981c3a7).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #870      +/-   ##
==========================================
+ Coverage   83.14%   83.20%   +0.06%     
==========================================
  Files         219      146      -73     
  Lines       16106    10740    -5366     
==========================================
- Hits        13391     8936    -4455     
+ Misses       2715     1804     -911     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.