[Doc] add notes on specialties on py-spy stack traces

[hongchaodeng]

Why are these changes needed?

Related issue number

Closes #43129

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    method in Tune, I've added it in doc/source/tune/api/ under the
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• Testing Strategy
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[scottsun94]

Thanks for the fix!

@rynewang Do you only want to add those notes to the documentation? Shall we also show them in the error message directly?

Failed to execute `['sudo', '-n', '/home/ray/anaconda3/bin/py-spy', 'record', '-o', PosixPath('/tmp/ray/session_2024-01-31_09-17-15_037017_341/logs/flamegraph_33695_cpu_profiling.svg'), '-p', '33695', '-d', '5', '-f', 'flamegraph']`.
- if you see "No such file or direction" in the stderr below, your worker process may have been exited. 
- If you see "No stack counts found" in the stderr below, your worker process may be sleeping and did not have activity in the last 5s.

=== stderr ===
[2024-01-31T22:37:27.932972718Z ERROR inferno::flamegraph] No stack counts found
Error: Failed to write flamegraph: I/O error: No stack counts found


=== stdout ===
py-spy> Sampling process 100 times a second for 5 seconds. Press Control-C to exit.

[rynewang]

LGTM. I wonder if we can also add it to the py-spy page, i.e. in

ray/dashboard/modules/reporter/profile_manager.py

Line 35 in 9a36755

def _format_failed_profiler_command(cmd, profiler, stdout, stderr) -> str:

[angelinalg]

Just a typo. Consider installing Vale, a lint checker for your text. There's a VSCode extension, too! go/vale