build(deps): bump actions/download-artifact from 7 to 8

Bumps [actions/download-artifact](https://github.com/actions/download-artifact) from 7 to 8.
- [Release notes](https://github.com/actions/download-artifact/releases)
- [Commits](actions/download-artifact@v7...v8)

---
updated-dependencies:
- dependency-name: actions/download-artifact
  dependency-version: '8'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

.github/workflows/build-sdk.yml

@@ -144,7 +144,7 @@ jobs:
           repository: ${{ env.BUILDSCRIPTS_REPO }}
           ref: ${{ needs.gate.outputs.buildscripts_revision }}
           fetch-depth: 0
-      - uses: actions/download-artifact@v7
+      - uses: actions/download-artifact@v8
         with:
           pattern: stage1-*
           path: artifacts
@@ -208,7 +208,7 @@ jobs:
           repository: ${{ env.BUILDSCRIPTS_REPO }}
           ref: ${{ needs.gate.outputs.buildscripts_revision }}
           fetch-depth: 0
-      - uses: actions/download-artifact@v7
+      - uses: actions/download-artifact@v8
         with:
           pattern: stage2-*
           path: artifacts
@@ -260,7 +260,7 @@ jobs:
           repository: ${{ env.BUILDSCRIPTS_REPO }}
           ref: ${{ needs.gate.outputs.buildscripts_revision }}
           fetch-depth: 0
-      - uses: actions/download-artifact@v7
+      - uses: actions/download-artifact@v8
         with:
           pattern: stage3-*
           path: artifacts
@@ -299,7 +299,7 @@ jobs:
       # two flat extractions into one directory overwrite each other's
       # provenance.json. Every artifact of this run is a stage artifact, and
       # more than one always exists, so this always nests per artifact name.
-      - uses: actions/download-artifact@v7
+      - uses: actions/download-artifact@v8
         with:
           path: artifacts
       - name: Group the release tree

.github/workflows/build.yml

@@ -102,7 +102,7 @@ jobs:
           libarchive-tools pkg-config
     # By stage, not by host name: which host produces stage 1 is the lock's
     # to say, and there is only ever one of them.
-    - uses: actions/download-artifact@v7
+    - uses: actions/download-artifact@v8
       with:
         pattern: stage1-*
         path: artifacts