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] <support@github.com>

Author: dependabot[bot]

.github/workflows/go-test.yml

@@ -46,7 +46,7 @@ jobs:
         with:
           go-version: stable
       - name: Download coverage artifacts
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v5
         with:
           path: cmd/firmware-action/coverage-reports
           merge-multiple: true

action.yml

@@ -57,7 +57,7 @@ inputs:
         option to just automatically download all available artifacts. This does not mean that they will
         be used during the build, but it means that you do not need to handle the downloading of artifacts
         yourself.
-      Internally a actions/download-artifact@v4 is used
+      Internally a actions/download-artifact@v5 is used
     required: false
     default: 'false'
   auto-upload-artifacts:
@@ -323,7 +323,7 @@ runs:
     # Docs: https://github.com/actions/download-artifact?tab=readme-ov-file#download-all-artifacts
 
     - name: download_artifacts
-      uses: actions/download-artifact@v4
+      uses: actions/download-artifact@v5
       if: inputs.auto-download-artifacts == 'true'
       with:
         path: .firmware-action2/