TEST/ASYNC: Larger threshold for timer tests.
TEST/ASYNC: Larger threshold for timer tests.

Addresses #111.

abouteiller/ucx,shssf/ucx,sergsagal1/ucx_rocm,biddisco/ucx,biddisco/ucx,shssf/ucx,sergsagal1/ucx_rocm,miked-mellanox/ucx,miked-mellanox/ucx,abouteiller/ucx,manjugv/ucx,abouteiller/ucx,biddisco/ucx,sergsagal1/ucx_rocm,miked-mellanox/ucx,shssf/ucx,manjugv/ucx,manjugv/ucx,abouteiller/ucx