fix InstanceDataCollectionCollection_CopyTo by retrying on 0 values

[smasher164]

Previously, when pcc.ReadCategory() returned 0 values, we did not retry,
which broke the test that asserted its length > 0. This time, we retry
when there are 0 values, by triggering the RetryHelper's exception
handler.

Fixes #68291

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Issue Details

---

Previously, when pcc.ReadCategory() returned 0 values, we did not retry,
which broke the test that asserted its length > 0. This time, we retry
when there are 0 values, by triggering the RetryHelper's exception
handler.

Fixes #68291

Author:	smasher164
Assignees:	-
Labels:	area-System.Diagnostics.PerformanceCounter
Milestone:	-

[ViktorHofer]

Thank you. LGTM

[danmoseley]

thanks!

[danmoseley]

Do we need the same fix at

runtime/src/libraries/System.Diagnostics.PerformanceCounter/tests/PerformanceCounterCategoryTests.cs

Line 299 in 1601356

InstanceDataCollectionCollection idColCol = pcc.ReadCategory();

?

Does this fix #60933 as well?

BTW, perf counter tests have had other random failures (eg #60933 (comment)) .. I'm not clear what is left after fixing ReadCategory(). in such cases it can be interesting to data dive into test history to see what failure modes there were. this can either be done with runfo or against the raw tables with Kusto. If at some point you're interested in learning how to get to this data, you can ask folks such as @ViktorHofer to show you how to use runfo, or I'd be happy to show you Kusto. either work.