Add GPU reverse mode to EnzymeExt (#454)

Co-authored-by: Michel Schanen <mschanen@anl.gov>
Co-authored-by: Valentin Churavy <vchuravy@users.noreply.github.com>

Author: 3 people

Diff for: .buildkite/pipeline.yml

@@ -50,7 +50,7 @@ steps:
       julia -e 'println("+++ :julia: Running tests")
                 using CUDA
                 include("test/extensions/enzyme.jl")
-                enzyme_testsuite(CUDABackend, CuArray, false)'
+                enzyme_testsuite(CUDABackend, CuArray, true)'
     agents:
       queue: "juliagpu"
       cuda: "*"