ci: Fix zephyr workflow

Updates the upload artifact version

Signed-off-by: Jamie McCrae <jamie.mccrae@nordicsemi.no>
(cherry picked from commit 84b56b6111)

.github/workflows/zephyr_build.yaml

@@ -94,7 +94,7 @@ jobs:
           ./scripts/twister --inline-logs -v -N -M --integration --overflow-as-errors --retry-failed 2 ${test_paths}
 
       - name: Upload Tests Results
-        uses: actions/upload-artifact@v2
+        uses: actions/upload-artifact@v4
         if: always()
         with:
           name: Tests Results