chore: set gcs-sdk-team as CODEOWNERS

[danielduhh]

replace outdated cloud-storage-dpe group

[bajajneha27]

@danielduhh There is an error popup asking if the new team exists and has the right permissions.

[BenWhitehead]

Looks like the build toolchain needs to be updated (I'm not sure how to do that) before the build can pass:

+ go get google.golang.org/genproto/...
go: downloading google.golang.org/genproto v0.0.0-20250303144028-a0af3efb3deb
go: downloading google.golang.org/genproto/googleapis/api v0.0.0-20250303144028-a0af3efb3deb
go: downloading google.golang.org/genproto/googleapis/rpc v0.0.0-20250303144028-a0af3efb3deb
go: pattern google.golang.org/genproto/...: google.golang.org/genproto@v0.0.0-20250303144028-a0af3efb3deb requires go >= 1.23.0 (running go 1.22.11; GOTOOLCHAIN=local)
go: pattern google.golang.org/genproto/...: google.golang.org/genproto/googleapis/api@v0.0.0-20250303144028-a0af3efb3deb requires go >= 1.23.0 (running go 1.22.11; GOTOOLCHAIN=local)
go: pattern google.golang.org/genproto/...: google.golang.org/genproto/googleapis/rpc@v0.0.0-20250303144028-a0af3efb3deb requires go >= 1.23.0 (running go 1.22.11; GOTOOLCHAIN=local)