build: fix maintenance script replacing too much strings

.github/scripts/update-version.sh

@@ -1,6 +1,6 @@
 if [ ! -z $(git diff --name-only HEAD HEAD~1 | grep build.gradle) ]; then
   new_version="$(git log -n1 --format=format:"%H")"
-  sed --in-place "s!//version:.*!//version: $new_version!g" build.gradle
+  sed --in-place "s!//^version:.*!//version: $new_version!g" build.gradle
   git add build.gradle
   git commit -m "[ci skip] update build script version to $new_version"
   git push