Build(deps): bump actions/download-artifact from 4 to 6

Bumps [actions/download-artifact](https://github.com/actions/download-artifact) from 4 to 6.
- [Release notes](https://github.com/actions/download-artifact/releases)
- [Commits](actions/download-artifact@v4...v6)

---
updated-dependencies:
- dependency-name: actions/download-artifact
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

.github/workflows/example_reusable-integration.yaml

@@ -174,7 +174,7 @@ jobs:
         with:
           fetch-depth: 1
       - name: Download All Matrix Artifacts
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v6
         with:
           path: build-artifacts
           merge-multiple: true

.github/workflows/reusable_deploy-artifacts.yaml

@@ -108,7 +108,7 @@ jobs:
           jf rt ping
 
       - name: Download artifacts
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v6
         with:
           name: ${{ inputs.gh-artifact-name }}
           path: ./build-artifacts

.github/workflows/reusable_sign-artifacts.yaml

@@ -72,7 +72,7 @@ jobs:
       CHECKOUT_REF: ${{ inputs.gh-workflows-ref }}
     steps:
       - name: Download Unsigned Artifacts
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v6
         with:
           name: ${{ inputs.gh-unsigned-artifacts }}
           path: unsigned-artifacts

.github/workflows/test_sign-artifacts-workflow.yaml

@@ -48,7 +48,7 @@ jobs:
         with:
           dotnet-version: 8.x
       - name: Download Signed Artifacts
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v6
         with:
           name: ${{ needs.test-sign-workflow.outputs.gh-artifact-name }}
           path: signed
@@ -76,7 +76,7 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v5
       - name: Download Test Fixtures
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v6
         with:
           name: test-fixtures
           path: test-fixtures