Update tests given recent changes to request building.

Now more methods have an EMPTY body by default.

It's inconvenient that we need to build the request that way, it would be much more reasonable to have a way to select the `EntityBody` in the builder and then have the right headers to be generated at the end.  I already have the change in a branch I'm working on but I want to see how the whole thing turns out before losing time to cherry pick the change.