ci: add luacheck

Author: GustavEikaas

.github/workflows/lint.yml

@@ -4,7 +4,6 @@ on:
   pull_request:
 
 jobs:
-
   lint:
     name: lint
     runs-on: ubuntu-latest

.github/workflows/luacheck.yml

@@ -0,0 +1,14 @@
+name: Luacheck
+
+on: [push, pull_request]
+
+jobs:
+  luacheck:
+    runs-on: ubuntu-latest
+    steps:
+
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Luacheck linter
+        uses: lunarmodules/luacheck@v1