fix(githooks): remove unnecessary newline in post-commit log output

.githooks/post-commit

@@ -11,13 +11,12 @@ GIT_LOCAL_ENV_VARS="$(git rev-parse --local-env-vars 2>/dev/null || true)"
 mkdir -p "$(dirname "$LOG_FILE")"
 
 {
-  echo ""
   echo "=== post-commit @ $(date +%Y-%m-%dT%H:%M:%S%z) ==="
   echo "repo:   $REPO_ROOT"
   echo "commit: $COMMIT_HASH"
   echo "script: $SCRIPT_PATH"
   echo ""
-} >> "$LOG_FILE"
+} > "$LOG_FILE"
 
 if [ ! -x "$SCRIPT_PATH" ]; then
   {