Inability to find SDK root/files in pkg/dartdev/test/native_assets/build_test and pkg/modular_test tests

[sstrickl]

The tests

pkg/dartdev/test/native_assets/build_test RuntimeError (expected Pass)
pkg/modular_test/test/find_sdk_root1_test RuntimeError (expected Pass)
pkg/modular_test/test/loader/loader_test RuntimeError (expected Pass)
pkg/modular_test/test/src/find_sdk_root2_test RuntimeError (expected Pass)

are failing on configurations

unittest-asserts-release-linux
unittest-asserts-release-win
unittest-asserts-release-mac

Example logs from each:

• pkg/dartdev/test/native_assets/build_test
• pkg/modular_test/test/find_sdk_root1_test
• pkg/modular_test/test/loader/loader_test
• pkg/modular_test/test/src/find_sdk_root2_test

Looking at the history, it looks like they went flaky after 089364b, so guessing it's the fileset change in that commit?

/cc @sortie

[sortie]

I did just encounter another test that failed when sharded because it couldn't locate the sdk root. Sounds like we got a few more of those cases around, which will cause problems like this when I move them between the local runs and the sharded runs. I'll take a look, thanks Tess :)