Disable h5a_iterate and h5l_iterate assertion tests

[mkitti]

Disable assertion tests for h5a_iterate and h5l_iterate while we investigate why these tests are being inconsistent.

Also perhaps @assert is not the best way to test if an error is being thrown.

[mkitti]

h5a_iterate: Test Failed at /home/runner/work/hdf5/hdf5/test/api.jl:41
  Expression: HDF5.API.h5a_iterate(f, HDF5.API.H5_INDEX_NAME, HDF5.API.H5_ITER_INC) do loc, name, info
    #= /home/runner/work/hdf5/hdf5/test/api.jl:44 =# @assert false
end
    Expected: AssertionError
  No exception thrown
Stacktrace:
 [1] macro expansion
   @ ~/work/hdf5/hdf5/test/api.jl:41 [inlined]
 [2] macro expansion
   @ /buildworker/worker/package_linux64/build/usr/share/julia/stdlib/v1.6/Test/src/Test.jl:1151 [inlined]
 [3] top-level scope
   @ ~/work/hdf5/hdf5/test/api.jl:4
h5l_iterate: Test Failed at /home/runner/work/hdf5/hdf5/test/api.jl:93
  Expression: HDF5.API.h5l_iterate(f, HDF5.API.H5_INDEX_NAME, HDF5.API.H5_ITER_INC) do loc, name, info
    return -1
end
    Expected: HDF5.API.H5Error
  No exception thrown
Stacktrace:
 [1] macro expansion
   @ ~/work/hdf5/hdf5/test/api.jl:93 [inlined]
 [2] macro expansion
   @ /buildworker/worker/package_linux64/build/usr/share/julia/stdlib/v1.6/Test/src/Test.jl:1151 [inlined]
 [3] top-level scope
   @ ~/work/hdf5/hdf5/test/api.jl:56