feat: Create all_data_requirements alias

[kevinpark1217]

Minor change.

I am creating a Python virtualenv with Bazel, and having all_data_requirements for data dependencies just like all_requirements would be very helpful.

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[kevinpark1217]

Hello @hrfuller @rickeylev, can I get a review?

[chrislovecnm]

How can we test this? Can we add something to one of our examples?

[kevinpark1217]

How can we test this? Can we add something to one of our examples?

Hi @chrislovecnm, I added a build_test() under examples/bzlmod. Also, examples/pip_parse_vendored/requirements.bzl shows the generated output.

[chrislovecnm]

LGTM - if you could add some documentation in the examples, that would rock!