The new vNext build system can run different build configurations in parallel (on different build agents) so you could, but I'm not sure how practical it would be.
Your tests sets would have to be in 4 different projects. Then you'd need to have different configurations:
- anycpu / release-with-tests1
- anycpu / release-with-tests2
- anycpu / release-with-tests3
- anycpu / release-with-tests4
With that you can enable (build) only 1 test project per configuration and set your build to run all tests (*test.dll), each configuration would only run one test project because the other ones were not built.
You enable the parallel build and it runs on up to 4 agents, depending on how many you have. Each agent would have to download the sources and build them before running the tests, so it could be interesting or not depending on how long your tests actually are.
There is a filter for the binaries you want to copy to your drop folder, so you can copy them for only 1 configuration and not waste disk space.