upgrade luacheck workflow and define std

.github/workflows/luacheck.yml

@@ -1,17 +1,10 @@
 name: luacheck
-
 on: [push, pull_request]
-
 jobs:
-  build:
-
+  luacheck:
     runs-on: ubuntu-latest
-
     steps:
-    - uses: actions/checkout@v1
-    - name: apt
-      run: sudo apt-get install -y luarocks
-    - name: luacheck install
-      run: luarocks install --local luacheck
-    - name: luacheck run
-      run: $HOME/.luarocks/bin/luacheck ./
+      - name: Checkout
+        uses: actions/checkout@main
+      - name: Luacheck
+        uses: lunarmodules/luacheck@master

.luacheckrc

@@ -1,3 +1,5 @@
+std = "min+minetest"
+
 unused_args = false
 max_line_length = 180
 
@@ -6,14 +8,6 @@ globals = {
 }
 
 read_globals = {
-	-- Stdlib
-	string = {fields = {"split"}},
-	table = {fields = {"copy", "getn"}},
-
-	-- Minetest
-	"vector", "ItemStack",
-	"dump",
-
 	-- optional deps
 	"advtrains",
 	"default",