change severity to warning

Signed-off-by: Yanxuan Liu <[email protected]>

Author: YanxuanLiu

.github/workflows/shell-check.yml

@@ -36,4 +36,4 @@ jobs:
       - name: Run ShellCheck
         uses: ludeeus/action-shellcheck@master
         with:
-          severity: error
+          severity: warning