[ci] Make sure the doc tarball is copied to the correct path

and not just called "download"

Author: dpiparo

.github/workflows/root-docs-ci.yml

@@ -163,4 +163,4 @@ jobs:
         aws s3 sync ${DOC_DIR}/html/ s3://root/doc/${WEB_DIR_NAME}/
         rm -rf ${DOC_DIR}/html
         aws s3 sync ${DOC_DIR}/ s3://root/doc/${WEB_DIR_NAME}/
-        aws s3 cp ${TAR_NAME}.gz s3://root/download
+        aws s3 cp ${TAR_NAME}.gz s3://root/download/