github/workflows: test with 1.24.x and 1.25.x

Always call http.Request.ParseForm method

Fix test: no need to repopulate the body with the Form

Set the request.Body to http.NoBody if request.Body is nil

recorder: specifying a cassette name is required

Also remove the `WithCassette` option.

CHANGELOG: document v4.0.0

Retract v3.2.1

Default Matcher with version v3.2.1 is stricter, so retract the version.

add NewMatcherFunc

Update CHANGELOG

Update changelog and add entry for v3.1.2