fix: update download URL for BCR presubmit check (#2337)

.bcr/source.template.json

diff --git a/.bcr/source.template.json b/.bcr/source.template.json
index 6767b68..866ee25 100644
--- a/.bcr/source.template.json
+++ b/.bcr/source.template.json
@@ -1,5 +1,5 @@
 {
   "integrity": "**leave this alone**",
   "strip_prefix": "",
-  "url": "https://github.com/{OWNER}/{REPO}/releases/download/{TAG}/{REPO}-{VERSION}.tar.gz"
+  "url": "https://github.com/{OWNER}/{REPO}/releases/download/{TAG}/{REPO}-v{VERSION}.tar.gz"
 }