chore(*): remove luarocks loader (#13608)

### Summary

This reduces memory usage a bit. I don't think we have any use for this anymore.

Signed-off-by: Aapo Talvensaari <aapo.talvensaari@gmail.com>

Author: bungle

bin/busted

@@ -72,8 +72,6 @@ if not os.getenv("KONG_BUSTED_RESPAWNED") then
   os.exit(rc)
 end
 
-pcall(require, "luarocks.loader")
-
 if os.getenv("BUSTED_EMMY_DEBUGGER") then
   emmy_debugger.init({
     debugger = os.getenv("BUSTED_EMMY_DEBUGGER"),

bin/kong

@@ -1,7 +1,6 @@
 #!/usr/bin/env resty
 
 setmetatable(_G, nil)
-pcall(require, "luarocks.loader")
 package.path = (os.getenv("KONG_LUA_PATH_OVERRIDE") or "") .. "./?.lua;./?/init.lua;" .. package.path
 require("kong.globalpatches")({ cli = true })
 math.randomseed() -- Generate PRNG seed
@@ -134,8 +133,6 @@ local args_str = table.concat(args_table, " ")
 local inline_code = string.format([[
 setmetatable(_G, nil)
 
-pcall(require, "luarocks.loader")
-
 package.path = (os.getenv("KONG_LUA_PATH_OVERRIDE") or "") .. "./?.lua;./?/init.lua;" .. package.path
 
 require("kong.cmd.init")("%s", %s)

kong/init.lua

@@ -27,9 +27,6 @@
 local pcall = pcall
 
 
-pcall(require, "luarocks.loader")
-
-
 assert(package.loaded["resty.core"], "lua-resty-core must be loaded; make " ..
                                      "sure 'lua_load_resty_core' is not "..
                                      "disabled.")