Fix the empty cipd_manifest

Change-Id: If1ddfcd4d95ece1e0debda79f691b1b932c97ac3
Reviewed-on: https://fuchsia-review.googlesource.com/c/drivers/misc/google/backlight/+/680132
Reviewed-by: Chase Latta <chaselatta@google.com>
diff --git a/scripts/emit_cipd_manifest.sh b/scripts/emit_cipd_manifest.sh
index 5ce1b89..3bbcb78 100755
--- a/scripts/emit_cipd_manifest.sh
+++ b/scripts/emit_cipd_manifest.sh
@@ -23,7 +23,7 @@
 }
 
 generate_upload_manifest() {
-  echo "{"files" : []}"
+  echo "{\"files\" : []}"
 }
 
 main() {