Update slsa-framework/slsa-github-generator action to v2

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
slsa-framework/slsa-github-generator	action	major	v1.10.0 -> v2.0.0

---

Release Notes

slsa-framework/slsa-github-generator (slsa-framework/slsa-github-generator)

v2.0.0

Compare Source

v2.0.0: Breaking Change: upload-artifact and download-artifact

• Our workflows now use the new @v4s of actions/upload-artifact and
  actions/download-artifact, which are incompatiblle with the prior @v3. See
  Our docs on the generic generator
  for more information and how to upgrade.

v2.0.0: Breaking Change: attestation-name Workflow Input and Output

• attestation-name as a workflow input to
  .github/workflows/generator_generic_slsa3.yml is now removed. Use
  provenance-name instead.

v2.0.0: DSSE Rekor Type

• When uploading signed provenance to the log, the entry created in the log is now
  a DSSE Rekor type. This fixes a bug where the current intoto type does not
  persist provenance signatures. The attestation will no longer be persisted
  in Rekor (#​3299)

---

Configuration

📅 Schedule: Branch creation - "before 4am on Monday" (UTC), Automerge - At any time (no schedule defined).

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

---

• If you want to rebase/retry this PR, check this box

---

This PR was generated by Mend Renovate. View the repository job log.