UCP: Fix pending op leak.
UCP: Fix pending op leak.

manjugv/ucx,manjugv/ucx,abouteiller/ucx,abouteiller/ucx,manjugv/ucx,biddisco/ucx,abouteiller/ucx,shssf/ucx,sergsagal1/ucx_rocm,sergsagal1/ucx_rocm,shssf/ucx,shssf/ucx,sergsagal1/ucx_rocm,biddisco/ucx,biddisco/ucx,abouteiller/ucx