[mojo-stdlib] Import what you use rather than from <module> import *

[StandinKP]

Fixes #2043

[gabrieldemarmiesse]

Hi, thank you for the pull request. It seems that the DCO is missing (the "signed-off-by" in commits). Please head to https://github.com/modularml/mojo/blob/main/CONTRIBUTING.md#signing-your-work and rectify the commit messages.

[StandinKP]

Hi, thank you for the pull request. It seems that the DCO is missing (the "signed-off-by" in commits). Please head to https://github.com/modularml/mojo/blob/main/CONTRIBUTING.md#signing-your-work and rectify the commit messages.

@gabrieldemarmiesse is this to be done for all commits or just should i add it to the last commit?

[gabrieldemarmiesse]

I believe it must be done on all commits, but it's not clear. For your information, I asked clarification questions to the maintainers here: #2060 and we should get better DX for DCO when completing #2057

[StandinKP]

Got it. Thanks. I have updated the commits

[JoeLoser]

The changes themselves look good, thank you! Just need to fix up the formatting:

mojo format -l 80
stdlib/test/builtin/test_simd.mojo
stdlib/test/builtin/test_string.mojo
stdlib/test/collections/test_set.mojo
stdlib/test/memory/test_memory.mojo
stdlib/test/pathlib/test_pathlib.mojo
stdlib/test/test_utils/types.mojo
stdlib/test/utils/test_tuple.mojo
stdlib/test/utils/test_variant.mojo

should do the trick for you.