[BugFix] Fix Ray collector example error

[albertbou92]

Description

This PR fixes one of the issues pointed out in #1862, caused by a change of the signature of the ray.wait() method in recent ray versions.

Motivation and Context

Why is this change required? What problem does it solve?
If it fixes an open issue, please link to the issue here.
You can use the syntax close #15213 if this solves the issue #15213

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Types of changes

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• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds core functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation (update in the documentation)
• Example (update in the folder of examples)

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• I have read the CONTRIBUTION guide (required)
• My change requires a change to the documentation.
• I have updated the tests accordingly (required for a bug fix or a new feature).
• I have updated the documentation accordingly.

[pytorch-bot]

🔗 Helpful Links

🧪 See artifacts and rendered test results at hud.pytorch.org/pr/pytorch/rl/1908

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✅ You can merge normally! (6 Unrelated Failures)

As of commit 711d741 with merge base 4d52d5f ():

FLAKY - The following jobs failed but were likely due to flakiness present on trunk:

• Continuous Benchmark (PR) / CPU Pytest benchmark (gh)
  Workflow failed! Resource not accessible by integration
• Continuous Benchmark (PR) / GPU Pytest benchmark (gh)
  Workflow failed! Resource not accessible by integration
• Habitat Tests on Linux / tests (3.9, 11.6) / linux-job (gh)
  RuntimeError: Command docker exec -t c3ee1eb3e2b43636b149f9de77ae33926909732c66df7bf46583e743c5913f61 /exec failed with exit code 139
• Unit-tests on Linux / tests-cpu (3.11) / linux-job (gh)
  test/test_rb.py::TestStorages::test_storage_dumps_loads[True-pytree-LazyTensorStorage-device_data0]
• Unit-tests on Linux / tests-gpu (3.8, 12.1) / linux-job (gh)
  test/test_env.py::TestLibThreading::test_auto_num_threads

BROKEN TRUNK - The following job failed but were present on the merge base:

👉 Rebase onto the `viable/strict` branch to avoid these failures

• Unit-tests on Windows / unittests-gpu / windows-job (gh)
  ##[error]The operation was canceled.

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[vmoens]

LGTM