Add outputs for the archive and checksum files

[matiaskorhonen]

Adds outputs from the action for the archive file name(s) and checksum file name(s).

This should enable using those in subsequent workflow steps, such as Artefact Attestations.

For example:

permissions:
  id-token: write
  contents: read
  attestations: write

#
# (the rest of the steps)
#

- uses: taiki-e/upload-rust-binary-action@v1
  id: upload-rust-binary-action
  with:
    dry-run: true
    bin: test-crate
    target: ${{ matrix.target }}
    build-tool: ${{ matrix.build_tool }}
    checksum: sha256,sha512,sha1,md5
    tar: all
    zip: all
    manifest-path: test-crate/Cargo.toml
    codesign: '-'

- name: Generate artifact attestation
  uses: actions/attest-build-provenance@v1
  with:
    subject-path: ${{ steps.upload-rust-binary-action.outputs.zip }}

# or

- name: Generate artifact attestation
  uses: actions/attest-build-provenance@v1
  with:
    subject-path: "${{ steps.upload-rust-binary-action.outputs.archive }}.*"

Hopefully I got most of the details right as I'm familiar with building GitHub Actions for the marketplace…

[taiki-e]

Thanks for the PR!

GITHUB_OUTPUT does not work on some self-hosted runners (https://github.com/taiki-e/create-gh-release-action/issues/17), so could you add a workaround for that problem (something like https://github.com/taiki-e/create-gh-release-action/commit/4466cb67b09ce43434d4955a48247d2af14993e6)?

Otherwise LGTM.

[taiki-e]

Published in 1.21.0.