update luacheck workflow

- change from `v1` to `master`
- rename build to luacheck
- remove stuff from luacheck config

.github/workflows/luacheck.yml

@@ -1,10 +1,10 @@
-name: Build
+name: luacheck
 on: [push, pull_request]
 jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@master
     - name: apt
       run: sudo apt-get install -y luarocks
     - name: luacheck install

.luacheckrc

@@ -1,21 +1,13 @@
 unused_args = false
-allow_defined_top = true
 
 globals = {
     "minetest",
 }
 
 read_globals = {
-    string = {fields = {"split"}},
-    table = {fields = {"copy", "getn"}},
-
 	-- Builtin
-    "vector", "ItemStack",
-    "dump", "DIR_DELIM", "VoxelArea", "Settings",
-
-    -- MTG
-    "default", "sfinv", "creative",
+	"ItemStack",
 	
 	-- Mod Deps
-	"technic"
+	"technic",
 }

README.md

@@ -1,6 +1,6 @@
 # Powerbanks [powerbanks]
 
-[![Build](https://github.com/OgelGames/powerbanks/workflows/Build/badge.svg)](https://github.com/OgelGames/powerbanks/actions)
+[![luacheck](https://github.com/OgelGames/powerbanks/workflows/luacheck/badge.svg)](https://github.com/OgelGames/powerbanks/actions)
 [![License](https://img.shields.io/badge/License-MIT%20and%20CC%20BY--SA%204.0-green.svg)](LICENSE.md)
 [![Minetest%20Forum](https://img.shields.io/badge/Minetest%20Forum-Feedback-lightgrey.svg)](https://forum.minetest.net/viewtopic.php?t=23791)
 [![ContentDB](https://content.minetest.net/packages/OgelGames/powerbanks/shields/downloads/)](https://content.minetest.net/packages/OgelGames/powerbanks/)