Testing light gbm bad allocation

[michaelgsharp]

Changes some of the LightGBM tests to run sequentially to try and fix the bad allocation issue.

This is in regards to issue #6961. I'll leave that issue open so we can continue to monitor after this goes in.

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Comparison is base (5e28578) 68.80% compared to head (b9e48ef) 68.81%. Report is 2 commits behind head on main.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #6968 +/- ## ======================================= Coverage 68.80% 68.81% ======================================= Files 1249 1249 Lines 249686 249686 Branches 25485 25485 ======================================= + Hits 171806 171814 +8 + Misses 71286 71282 -4 + Partials 6594 6590 -4 ``` | [Flag](https://app.codecov.io/gh/dotnet/machinelearning/pull/6968/flags?src=pr&el=flags&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=dotnet) | Coverage Δ | | |---|---|---| | [Debug](https://app.codecov.io/gh/dotnet/machinelearning/pull/6968/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=dotnet) | `68.81% <100.00%> (+<0.01%)` | :arrow_up: | | [production](https://app.codecov.io/gh/dotnet/machinelearning/pull/6968/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=dotnet) | `63.28% <ø> (+<0.01%)` | :arrow_up: | | [test](https://app.codecov.io/gh/dotnet/machinelearning/pull/6968/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=dotnet) | `88.41% <100.00%> (ø)` | | Flags with carried forward coverage won't be shown. [Click here](https://docs.codecov.io/docs/carryforward-flags?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=dotnet#carryforward-flags-in-the-pull-request-comment) to find out more. | [Files](https://app.codecov.io/gh/dotnet/machinelearning/pull/6968?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=dotnet) | Coverage Δ | | |---|---|---| | [test/Microsoft.ML.TestFramework/BaseTestClass.cs](https://app.codecov.io/gh/dotnet/machinelearning/pull/6968?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=dotnet#diff-dGVzdC9NaWNyb3NvZnQuTUwuVGVzdEZyYW1ld29yay9CYXNlVGVzdENsYXNzLmNz) | `88.23% <100.00%> (ø)` | | | [...osoft.ML.Tests/TrainerEstimators/TreeEstimators.cs](https://app.codecov.io/gh/dotnet/machinelearning/pull/6968?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=dotnet#diff-dGVzdC9NaWNyb3NvZnQuTUwuVGVzdHMvVHJhaW5lckVzdGltYXRvcnMvVHJlZUVzdGltYXRvcnMuY3M=) | `97.84% <ø> (ø)` | | ... and [3 files with indirect coverage changes](https://app.codecov.io/gh/dotnet/machinelearning/pull/6968/indirect-changes?src=pr&el=tree-more&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=dotnet)

[michaelgsharp]

/azp run

[azure-pipelines[bot]]

Azure Pipelines successfully started running 2 pipeline(s).

[michaelgsharp]

/azp run

[azure-pipelines[bot]]

Azure Pipelines successfully started running 2 pipeline(s).

[michaelgsharp]

/azp run

[azure-pipelines[bot]]

Azure Pipelines successfully started running 2 pipeline(s).

[michaelgsharp]

/azp run

[azure-pipelines[bot]]

Azure Pipelines successfully started running 2 pipeline(s).

[ericstj]

Just saw this in 3.0 branch Code Coverage build. Maybe we should backport this test reliability fix?

[ericstj]

/backport to release/3.0

[github-actions[bot]]

Started backporting to release/3.0: https://github.com/dotnet/machinelearning/actions/runs/8272862595