Bump actions/download-artifact from 2 to 4.1.7 in /.github/workflows

Bumps [actions/download-artifact](https://github.com/actions/download-artifact) from 2 to 4.1.7.
- [Release notes](https://github.com/actions/download-artifact/releases)
- [Commits](actions/download-artifact@v2...v4.1.7)

---
updated-dependencies:
- dependency-name: actions/download-artifact
  dependency-type: direct:production
...

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

.github/workflows/SnoopCompile.yml

@@ -73,7 +73,7 @@ jobs:
     steps:
       - uses: actions/checkout@v2
       - name: Download all
-        uses: actions/download-artifact@v2
+        uses: actions/download-artifact@v4.1.7
 
       - name: CompileBot postprocess
         run: julia -e 'using Pkg; Pkg.add( PackageSpec(name="CompileBot", rev = "master") );