tests: "debug type 'coreclr' is not supported" in integ CI logs

# Problem

```
2023-11-02 18:22:05 [ERROR]: SamLaunchRequestError: Failed to run launch configuration
-> Error: DialogService: refused to show dialog in tests. Contents: DialogService: refused to show dialog in tests. Contents: Configured debug type 'coreclr' is not supported.
✔ target=template: invokes and attaches on debug request (F5) (7592ms)
```

https://github.com/dotnet/vscode-csharp/issues/5402 has some discussion about DLL locations. But in our case the more likely answer is that the .NET vscode extension is not installing properly or is not auto-installing necessary things, or something like that.

Oh wait, we aren't installing the dotnet extension here: https://github.com/aws/aws-toolkit-vscode/blob/106666e0bbac3236b7ef50f45dd81634d6441d05/scripts/test/launchTestUtilities.ts#L119-L130

# Expected behavior

- determine whether this should be a test failure
- detect the conditions that should (or shouldn't) fail and adjust the test logic.
- if the test _should_ be failing:
1. ensure the test fails correctly (currently it appears to be passing)
2. fix the cause of the failure
- if the test _should not_ be failing (i.e. the "coreclr is not supported" message is a false signal):
- adjust the test logic so that this misleading message does not appear in the test logs.

Inspect the referenced setup in scripts/test/launchTestUtilities.ts at lines 119-130, then trace the `target=template` debug request (F5) integration test and its CI log handling. Determine whether the unsupported `coreclr` message indicates a real failure, and make the test outcome and logging match that decision.

Written by the indexing model from the issue text.