Revert "[lit] Temporarily disable shtest-timeout.py on darwin"

This reverts commit 771829b640a5494ab65c810dd6b4330522bf3a33 (rr328598)

Hopefully the test will now pass on the bots.

rdar://problem/38774530

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@328703 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed