refactor: replaced heap mock with Linux-compatible heap component

host_test/CMakeLists.txt

@@ -3,7 +3,6 @@ cmake_minimum_required(VERSION 3.16)
 include($ENV{IDF_PATH}/tools/cmake/project.cmake)
 set(COMPONENTS mqtt main)
 list(APPEND EXTRA_COMPONENT_DIRS
-                                 "mocks/heap/"
                                  "$ENV{IDF_PATH}/tools/mocks/esp_hw_support/"
                                  "$ENV{IDF_PATH}/tools/mocks/freertos/"
                                  "$ENV{IDF_PATH}/tools/mocks/esp_timer/"

host_test/mocks/heap/CMakeLists.txt

@@ -1,4 +0,0 @@
-idf_component_get_property(original_heap_dir heap COMPONENT_OVERRIDEN_DIR)
-
-idf_component_register(SRCS heap_mock.c
-  INCLUDE_DIRS "${original_heap_dir}/include")

host_test/mocks/heap/heap_mock.c

@@ -1,11 +0,0 @@
-#include "esp_heap_caps.h"
-#include <stdint.h>
-#include <stdlib.h>
-
-
-
-void *heap_caps_calloc(size_t n, size_t size, uint32_t caps) {
-  (void)caps;
-  return calloc(n, size);
-
-}