fix(datastore): remove namespace from Key.String() (#10684)

[sgp]

Datastore namespaces may be sensitive, and it's best not to emit them.

Provide a datastore.Key.StringWithNamespace() as an alternative, and use this version internally, which preserves the fix from https://github.com/googleapis/google-cloud-go/issues/7829.

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[bhshkh]

Please create a bug describing the issue.

[sgp]

Please create a bug describing the issue.

I did, didn't I? It's #10684.

[sgp]

I've addressed your comments, @bhshkh -- let me know what you think.

[bhshkh]

I've addressed your comments, @bhshkh -- let me know what you think.

Thanks! LGTM

[bhshkh]

This branch is out-of-date with the base branch. To minimize friction, consider setting 'Allow edits from maintainers' on the PR, which will enable project committers and automation to update your PR. To allow edits, see point 4 at https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/working-with-forks/allowing-changes-to-a-pull-request-branch-created-from-a-fork#enabling-repository-maintainer-permissions-on-existing-pull-requests

[sgp]

@bhshkh --

To minimize friction, consider setting 'Allow edits from maintainers' on the PR, which will enable project committers and automation to update your PR.

Sadly, I created this fork from inside our organization, and apparently according to Github:

You cannot give push permissions to a fork owned by an organization.

I could close this PR, fork using my personal repository, and then recreate the PR there. That's a pain, and we would lose the conversation here.

In the meantime, can you force Kokoro to run so this will merge? Everything else has passed.

[sgp]

Ok, apparently this is a losing battle, as I cannot continually fight the progress of the monorepo changing every day. I'm going to close this PR and reopen it using a personal fork where I can give appropriate permissions.