Add CI for nightly and fix time_start

[vchuravy]

ERROR: LoadError: setfield!: const field .time_start of type DefaultTestSet cannot be changed

As seen on JuliaGPU/GPUCompiler.jl#731

[giordano]

I see, that was changed in JuliaLang/julia#59374, but should be easy to fix, I can take care of it in a bit.

[giordano]

After #22 I get

basic: Error During Test at none:1
  Got exception outside of a @test
  On worker 2:
  MethodError: no method matching ParallelTestRunner.TestRecord(::Test.DefaultTestSet, ::Float64, ::Int64, ::Float64, ::Base.GC_Diff, ::Int64, ::Float64, ::Float64, ::UInt64)
  The type `ParallelTestRunner.TestRecord` exists, but no method is defined for this combination of argument types when trying to construct it.
  Closest candidates are:
    ParallelTestRunner.TestRecord(::Any, ::Any, ::Any, ::Any, ::Any)
     @ ParallelTestRunner ~/.julia/dev/ParallelTestRunner/src/ParallelTestRunner.jl:68
    ParallelTestRunner.TestRecord(::Any, ::Float64, ::UInt64, ::Float64, ::UInt64)
     @ ParallelTestRunner ~/.julia/dev/ParallelTestRunner/src/ParallelTestRunner.jl:68
  Stacktrace:
   [1] inner
     @ ~/.julia/dev/ParallelTestRunner/src/ParallelTestRunner.jl:181
   [2] runtest
     @ ~/.julia/dev/ParallelTestRunner/src/ParallelTestRunner.jl:189
   [3] #handle_msg##4
     @ ~/repo/julia/usr/share/julia/stdlib/v1.13/Distributed/src/process_messages.jl:287
   [4] run_work_thunk
     @ ~/repo/julia/usr/share/julia/stdlib/v1.13/Distributed/src/process_messages.jl:70
   [5] #handle_msg##2
     @ ~/repo/julia/usr/share/julia/stdlib/v1.13/Distributed/src/process_messages.jl:287

Test Summary: | Error  Total  Time
  Overall     |     1      1  1.6s
    basic     |     1      1
    FAILURE

There are other upstream changes we need to adapt to, but at least note that the time is now set and printed correctly 😀