refactor(tools): simplify the logic of request_aware_table (#11756)

There are some duplicated code in tracing.request_id and request_aware_table,
use request_id.get() to get clean code.

kong/tools/request_aware_table.lua

@@ -5,37 +5,28 @@ local table_new = require("table.new")
 local table_clear = require("table.clear")
 local get_request_id = require("kong.tracing.request_id").get
 
+
 local is_not_debug_mode = (kong.configuration.log_level ~= "debug")
 
 
 local error        = error
 local rawset       = rawset
 local setmetatable = setmetatable
-local get_phase    = ngx.get_phase
-
-
-local NGX_VAR_PHASES = {
-  set           = true,
-  rewrite       = true,
-  access        = true,
-  content       = true,
-  header_filter = true,
-  body_filter   = true,
-  log           = true,
-  balancer      = true,
-}
+
+
 local ALLOWED_REQUEST_ID_K = "__allowed_request_id"
 
 
 -- Check if access is allowed for table, based on the request ID
 local function enforce_sequential_access(table)
-  if not NGX_VAR_PHASES[get_phase()] then
+  local curr_request_id = get_request_id()
+
+  if not curr_request_id then
     -- allow access and reset allowed request ID
     rawset(table, ALLOWED_REQUEST_ID_K, nil)
     return
   end
 
-  local curr_request_id = get_request_id()
   local allowed_request_id = rawget(table, ALLOWED_REQUEST_ID_K)
   if not allowed_request_id then
     -- first access. Set allowed request ID and allow access

kong/tracing/request_id.lua

@@ -2,6 +2,7 @@ local ngx = ngx
 local var = ngx.var
 local get_phase = ngx.get_phase
 
+
 local NGX_VAR_PHASES = {
   set           = true,
   rewrite       = true,