This PR fixes the ASAN failure in
https://github.com/llvm/llvm-project/pull/90930.
The original PR made the assumption that parent
`ThreadPlanStepOverRange`'s lifetime will always be longer than
`ThreadPlanSingleThreadTimeout` leaf plan so it passes the
`m_timeout_info` as reference to it.
From the ASAN failure, it seems that this assumption may not be true
(likely the thread stack is holding a strong reference to the leaf
plan).
This PR fixes this lifetime issue by using shared pointer instead of
passing by reference.
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Co-authored-by: jeffreytan81 <jeffreytan@fb.com>
128ef9eb53