Bump actions/download-artifact from 5 to 6

Bumps [actions/download-artifact](https://github.com/actions/download-artifact) from 5 to 6.
- [Release notes](https://github.com/actions/download-artifact/releases)
- [Commits](actions/download-artifact@v5...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/CI.yml

@@ -279,7 +279,7 @@ jobs:
 
     - name: Download Artifacts
       id: download_windows_artifacts
-      uses: actions/download-artifact@v5
+      uses: actions/download-artifact@v6
       with:
         path: ${{ github.workspace }}
         pattern: fpm-*-windows-*-gcc-${{ matrix.gcc_v }}.exe
@@ -396,7 +396,7 @@ jobs:
       if: ${{ github.event_name == 'push' }}
 
     - name: Download Artifacts
-      uses: actions/download-artifact@v5
+      uses: actions/download-artifact@v6
       with:
         path: fpm-cd-artifacts
         pattern: 'fpm-*-gcc-12*'

.github/workflows/release.yml

@@ -128,7 +128,7 @@ jobs:
       if: ${{ github.event_name == 'push' }}
 
     - name: Download Artifacts
-      uses: actions/download-artifact@v5
+      uses: actions/download-artifact@v6
       with:
         path: fpm-cd-artifacts
         merge-multiple: true