[core] Fix bugs in data locality (#24698)

[stephanie-wang]

Why are these changes needed?

Redo for PR #24698:

This fixes two bugs in data locality:

• When a dependent task is already in the CoreWorker's queue, we ran the data locality policy to choose a raylet before we added the first location for the dependency, so it would appear as if the dependency was not available anywhere.
• The locality policy did not take into account spilled locations.

Added C++ unit tests and Python tests for the above.

Split test_reconstruction to avoid test timeout. I believe this was happening because the data locality fix was causing extra scheduler load in a couple of the reconstruction stress tests.

[mwtian]

I think we need to add python/ray/tests/test_reconstruction_2.py to a build target, e.g. large_size_python_tests_shard_0