New threadpool, fixed in NR UE

This merge request is an attempt to fix the new thread pool implementation for use in NR UE and gNB (as well as eNB).

common/utils/actor/tests/CMakeLists.txt

+add_executable(test_actor test_actor.cpp)
+target_link_libraries(test_actor PRIVATE actor GTest::gtest thread-pool LOG)
+add_dependencies(tests test_actor)
+add_test(NAME test_actor
+  COMMAND ./test_actor)