[v3] Fix some untyped defs

[dstansby]

Some of the easier fixes for some of the untyped definitions.

[pep8speaks]

Hello @dstansby! Thanks for updating this PR. We checked the lines you've touched for PEP 8 issues, and found:

• In the file src/zarr/_storage/store.py:

Line 356:36: E203 whitespace before ':'

Comment last updated at 2024-04-14 08:26:13 UTC

[jhamman]

@dstansby -- first, thanks for the continued effort here. With #1809 in, you have a few conflicts to resolve. I also think you can stop making changes to everything in the v2 directory going forward. We plan to remove that code path once the v3 effort wraps up.

[dstansby]

Good to know! I think all the changes here are now redundant, so I'll close.