build(deps): bump actions/download-artifact from 4 to 5

Bumps [actions/download-artifact](https://github.com/actions/download-artifact) from 4 to 5.
- [Release notes](https://github.com/actions/download-artifact/releases)
- [Commits](actions/download-artifact@v4...v5)

---
updated-dependencies:
- dependency-name: actions/download-artifact
  dependency-version: '5'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

.github/workflows/deploy-verification.yml

@@ -174,7 +174,7 @@ jobs:
       uses: actions/checkout@v4
 
     - name: Download verification artifacts
-      uses: actions/download-artifact@v4
+      uses: actions/download-artifact@v5
       with:
         name: deployment-verification-${{ github.run_number }}
 
@@ -238,7 +238,7 @@ jobs:
       uses: actions/checkout@v4
 
     - name: Download verification artifacts
-      uses: actions/download-artifact@v4
+      uses: actions/download-artifact@v5
       with:
         name: deployment-verification-${{ github.run_number }}
 
@@ -331,7 +331,7 @@ jobs:
       uses: actions/checkout@v4
 
     - name: Download verification artifacts
-      uses: actions/download-artifact@v4
+      uses: actions/download-artifact@v5
       with:
         name: deployment-verification-${{ github.run_number }}
 

.github/workflows/kani-regression.yml

@@ -231,7 +231,7 @@ jobs:
       uses: actions/checkout@v4
 
     - name: Download all KANI results
-      uses: actions/download-artifact@v4
+      uses: actions/download-artifact@v5
       with:
         pattern: kani-results-*
         merge-multiple: true

.github/workflows/kani-verification.yml

@@ -260,7 +260,7 @@ jobs:
           echo "✅ All verification jobs completed successfully"
       
       - name: Download All Reports
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v5
         with:
           pattern: kani-report-*
           merge-multiple: true