74f58198fd
As the DSL internally calls `ResultActions.andExpect`, this is done with a trick where a synthetic `ResultActions` is provided at top level which stores each `ResultMatcher` in a mutable list. Once the DSL usage is done, the top level DSL `andExpectAll` turns that list into a `vararg` passed down to the actual `actions.andExpectAll`. Closes gh-27317