Update build.yml

Signed-off-by: Michal <michal@tar.black>

.github/workflows/build.yml

@@ -35,7 +35,9 @@ jobs:
          
          # Build ISO and rename to match BUILD_DATE
          bash build.sh --build-iso
-         mv *.iso crystal-live-${BUILD_DATE}-x86_64.iso 2> /dev/null
+         if [[ ! "${ls *.iso)" == "crystal-live-${BUILD_DATE}-x86_64.iso ]]; then
+             mv *.iso crystal-live-${BUILD_DATE}-x86_64.iso
+         fi
          md5sum *.iso > MD5SUM-iso
          
          # Remove chrooted.sh in between operations
@@ -44,7 +46,7 @@ jobs:
          # Likewise, but for the rootfs
          bash build.sh --build-bootstrap
          md5sum *.tar.gz > MD5SUM-rootfs
-         mv *.tar.gz crystal-rootfs-${BUILD_DATE}-x86_64.tar.gz 2> /dev/null
+         mv *.tar.gz crystal-rootfs-${BUILD_DATE}-x86_64.tar.gz
          
          # Set upload name to BUILD_DATE
          echo "::set-output name=date::${BUILD_DATE}"