fix luarocks to 3.12.2

Author: chensunny

.github/workflows/test.yml

@@ -11,6 +11,8 @@ jobs:
       with:
         luaVersion: "luajit-openresty"
     - uses: leafo/gh-actions-luarocks@v5
+      with:
+        luarocksVersion: "3.12.2"
     - run: luarocks install luacheck
     - run: luacheck lib