refactor(base.lua): improve test completion logic

Refactored the test completion logic in the `run_tests` function for better readability and maintainability. Removed redundant check for `minetest.settings:get_bool("test_harness_stop_server", true)` and streamlined the conditional flow based on `tests_state`. This change enhances code clarity without altering functionality significantly.

.util/docker-compose.yaml

@@ -1,7 +1,7 @@
 version: "3.2"
 services:
   server:
-    restart: no
+    restart: "no"
     build:
       dockerfile: Dockerfile
     ports:

base.lua

@@ -554,11 +554,9 @@ local run_tests = function()
         end
 
         print("Server tests done, " .. failed .. " tests failed.")
-        if minetest.settings:get_bool("test_harness_stop_server", true) and ( next(players_tests) == nil or tests_state == TESTS_STATE_ENUM.DONE) then
-            request_shutdown()
-        end
 
-        if tests_state == TESTS_STATE_ENUM.DONE then
+        if next(players_tests) == nil or tests_state == TESTS_STATE_ENUM.DONE then
+            set_tests_done()
             return
         end