Quieter tests

[IanButterworth]

• Quiets intentional depwarns by catching and testing for them

From worker 5:	┌ Warning: `old_return_args` is deprecated, use `new_return_args` instead.
From worker 5:	│   caller = macro expansion at Test.jl:478 [inlined]
From worker 5:	└ @ Core /cache/build/default-amdci5-0/julialang/julia-master/julia-4d8c22f7f6/share/julia/stdlib/v1.10/Test/src/Test.jl:478
From worker 5:	┌ Warning: `old_return_args` is deprecated, use `new_return_args` instead.
From worker 5:	│   caller = macro expansion at Test.jl:478 [inlined]
From worker 5:	└ @ Core /cache/build/default-amdci5-0/julialang/julia-master/julia-4d8c22f7f6/share/julia/stdlib/v1.10/Test/src/Test.jl:478

• Groups the threaded tests into a single report per nthreads tested

• Catches what seem to be intentional unused type variable warnings

From worker 11:	WARNING: method definition for ambig_with_bounds at /cache/build/default-amdci5-0/julialang/julia-master/julia-4d8c22f7f6/share/julia/test/ambiguous.jl:49 declares type variable S but does not use it.
From worker 11:	WARNING: method definition for ambig_with_bounds at /cache/build/default-amdci5-0/julialang/julia-master/julia-4d8c22f7f6/share/julia/test/ambiguous.jl:50 declares type variable S but does not use it.
From worker 11:	WARNING: method definition for f11407 at /cache/build/default-amdci5-0/julialang/julia-master/julia-4d8c22f7f6/share/julia/test/ambiguous.jl:388 declares type variable V but does not use it.
From worker 11:	WARNING: method definition for f11407 at /cache/build/default-amdci5-0/julialang/julia-master/julia-4d8c22f7f6/share/julia/test/ambiguous.jl:388 declares type variable K but does not use it.
From worker 11:	WARNING: method definition for stripType at /cache/build/default-amdci5-0/julialang/julia-master/julia-4d8c22f7f6/share/julia/test/ambiguous.jl:403 declares type variable T but does not use it.
From worker 13:	WARNING: method definition for bad_tvars at /cache/build/default-amdci5-0/julialang/julia-master/julia-4d8c22f7f6/share/julia/test/core.jl:5270 declares type variable T but does not use it.
From worker 13:	WARNING: method definition for bad_tvars2 at /cache/build/default-amdci5-0/julialang/julia-master/julia-4d8c22f7f6/share/julia/test/core.jl:5273 declares type variable T but does not use it.

[fredrikekre]

Failures look related:

ERROR: LoadError: syntax: "module" expression not at top level
in expression starting at 
/cache/build/default-amdci5-7/julialang/julia-master/julia-10cb68f4a3/share/julia/test/threads_exec.jl:30