test-execute: use CPUSet too
    
    cpu_set_malloc() was the last user. It doesn't seem useful to keep
    it just to save the allocation of a few hundred bytes in a test, so
    it is dropped and a fixed maximum is allocated (1024 bytes).
    
    (cherry picked from commit 167a776dbe9d033523bd6881e5a695f2155dc321)
    
    Related: #1734787
    
    patch_name: 0279-test-execute-use-CPUSet-too.patch
    present_in_specfile: true
    location_in_specfile: 279
    squash_commits: true